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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.
211

Monitorování chemických parametrů povrchových důlních vod z hyperspektrálních obrazových dat / Monitoring of chemical parameters of mining waters from hyperspectral image data

Hladíková, Lenka January 2012 (has links)
Monitoring of Chemical Parameters of Mining Waters from Hyperspectral Image Data Abstract The thesis deals with utilization of hyperspectral image data for mining water quality monitoring. Sokolov lignite basin, facing many environmental problems caused by brown coal mining activities is the area of interest. Airborne hyperspectral image data acquired by the HyMap sensor in 2009 and 2010 and ground truth data - chemical and physical parameters of water samples are the main data sources for the thesis. Practical part aims at estimating of the amount of the dissolved iron and suspended sediments in selected water bodies. Two approaches were used to achieve this goal - the empirically derived relationship between the ground measurements and reflectance of the water bodies, and spectral unmixing method. Comparison of the two mentioned approaches and evaluation of validity to use the proposed methods for the data acquired by the same sensor one year later is also a part of this thesis.
212

Prameny radioaktivních minerálních vod v oblasti tanvaldského granitu / Springs of the radioactive mineral waters on Tanvald granite

Kohn, Pavel January 2015 (has links)
In the years 2014-2015 a radiohydrogeochemical survey was carried out in the Tanvald granite body. Tanvald granite is a two-mica granite body located on the southern edge of the Krkonoše-Jizera Pluton, in the Lusatian part of the Saxony and Thuringian zone of the Variscan orogenic belt. The aim of the survey was to find radioactive water, the 222 Rn volume activity of which exceeds 1500 Bq/l. Such water is - under the Act no. 164/2001 Coll. - considered as radioactive mineral water. The result was a found of 20 water sources meeting this condition and many other sources approaching this value. In terms of the findings, the most important area is Dlouhý Most, where 8 of the radioactive water resources exceeding 1500 Bq/l were found. The most important of these is probably the source TGR/11 with the 222 Rn volume activity 2449 Bq/l. A cluster of water sources with a slightly higher conductivity (exceeding 300 µS/cm) appears in the Dlouhý Most area. Chemical analysis of the most important of them (TG1/15) showed that it is water of the Na-Ca-Cl type, probably contaminated by a run-off from the motorway, which is salted in winter. Another important site is the Kokonín fault area. At this important geological structure a total of four springs of radioactive water with the 222 Rn volume activity greater...
213

Dlouhodobý vývoj kvality vody rybníka Svět ve vztahu k rybářskému hospodaření / Long-term trends in water quality of pond Světin relation to fish management

Altmann, Martin January 2016 (has links)
Fishpond ecosystems provide many other services besides fish production. One of them is the retention of nutrients and thus ability to change the quality of the through flowing water, thereby ability to influence the overall quality of surface waters. In the case of the fishpond Svět in Třeboň it is also recreation, as the pond is an integral part of the tourism of the town. Water quality in the fishpond and its retention capacity of phosphorus is connected with the fish management and the inflow of nutrients from the catchment basis, especially within a cascade of ponds and densely populated or agricultural regions. This thesis evaluates seasonal (2013, 2015) and long term (2007-2015) trend of water quality of pond Svět in Třeboň in relation to fish management. Furthermore, mass balance was calculated for 2015 and estimated for 2013. The years 2015 and 2013 (the first years of production cycle) varied considerably in amount of annual rainfall. The year 2015 was extremely dry and 2013 very aqueous. Different hydrological conditions caused different seasonal courses in hydrochemistry parameters and its concentrations. The water quality of fishpond Svět is in the most of parameters better in comparison with other production fishponds in the Třeboň region and also the intensity of fish management is...
214

Léčivé radioaktivní minerální prameny v oblasti Skalná - Bad Brambach / Radioactive medicinal springs in the Skalná - Bad Brambach area

Turnová, Štěpánka January 2019 (has links)
Radiohydrochemical exploration took place in east part of the "smrčinský" pluton between "Skalná-Plesná-Bad Brambach in years 2016-2018. The main aim of the exploration was location and thorough research of possible occurrence of waters with radioactive concretation higher than 1500 Bq/l. That is a value for radioactive mineral waters given by the "lázeňským" law number 164/2001 Sb. Most important area is Plesná-south where was discovered several springs with values exceeding 5000 Bq/l. Eminent spring is called "Břetislav-Radonka" and lies one kilometre southwest from the train station Plesná-Šneky with an activity of about 12.5 kBq / l 222 Rn and a flow rate of about 2.5 l / min. It is the most active surface discharge of radon mineral water in the Czech Republic Another significant source area is north of Skalna - north. These springs were discovered almost 60 years ago, Dr. Marie Zukriegelová. The main source of this area was named after its discoverer - the "Marie Z" spring with an activity of 5800 Bq / l 222 Rn.Further the research focused on historical radioactive conduit which were used to supply village Skalné with water. The conduit was separated on two "branches" and the younger one was built ten years after the first one. In both pipes were found radioactive waters and the most important...
215

Úloha Aquaporin 4 kanálů a Transient Receptor Potential Vanilloid 4 kanálů při objemových změnách astrocytů / The Role of Aquaporin 4 channels and Transient Receptor Potential Vanilloid 4 channels in astrocytic swelling

Heřmanová, Zuzana January 2019 (has links)
Astrocytes posses a wide range of functions within the brain. In response to ischemic conditions they swell due to increased uptake of osmolytes and they are mainly responsible for cytotoxic edema formation. However, they are also able to regulate their volume by releasing osmolytes together with water via the process of regulatory volume decrease (RVD). The Aquaporin 4 (AQP4) channel and Transient receptor potential vanilloid 4 (TRPV4) channel are suspected to be strongly involved in these processes of astrocytic volume regulation. The goal of the present diploma thesis was to clarify the role of both channels in astrocytic swelling in situ. For our experiments we used a subpopulation of green fluorescent protein-labelled astrocytes from AQP4-deficient (AQP4-/- ), TRPV4-deficient (TRPV4-/- ) and control (Ctrl) mice. Cell volume alterations were induced in acute brain slices by hypoosmotic stress or by oxygen-glucose deprivation (OGD). Data were quantified using fluorescence intensity-based approach in the whole cells and in astrocytic endfeet. Our results indicate, that there is no difference in astrocytic swelling or cell volume recovery between astrocytes from AQP4-/- , TRPV4-/- and control mice when exposed to hypoosmotic stress. On the contrary, volume changes induced by OGD varied...
216

Využití přečištěných odpadních vod pro kapkovou závlahu / Utilization of treated wastewater in a drip irrigation system

Šalanda, Pavel January 2020 (has links)
Drought has an increasing importance in the Czech republic. It is necessary to look for potential irrigation water sources, which are important for agriculture. Treated wastewater can be one of them. It has potentially negative impact on soil physico-chemical properties, which is well-known from many researches in arid regions. The aim of this diploma thesis was to investigate, if the drip irrigation with treated wastewater (from constructed wetland) also has a potentially negative impact on two soils in the Czech republic. In one year experiment drip irrigation with treated wastewater was carried out in the greenhouse. Four treatments of irrigation was used for both soils - irrigation with treated wastewater, irrigation with groundwater, irrigation with treated wastewater + rainwater, irrigation with groundwater + rainwater. An amount of rainwater correspond with total precipitation of two locations, where the soils were brought from (Kostelec nad Ohří - Ústí nad Labem region and Hostětín - Zlín region). pH and electrical conductivity of soil leachate, total concentration of Na, K, Ca, Mg a P, bulk density, particle density and porosity was measured in both soils in 5 and 10 centimeters from source of irrigation. Values of pH of soil leachate fluctuated in every treatment in both soils during the...
217

Efekt kosmetických přípravků s různým pH na vlastnosti kůže mužů a žen / The effect of cosmetic products with different pH on the skin properties of men and women

Drabová, Veronika January 2019 (has links)
The aim of this diploma thesis was to summarize the basic knowledge of human skin and it's biophysical parameters. Attention was focused on influence of cosmetic products with different pH on the change of skin parameters especially. The first part describes the anatomical and histological structure of the skin, it's basic functions and development. In the following chapters of this work is mentioned physiological representation of microorganisms found on the skin surface and general characteristics of cosmetic products. There are used in everyday skin care that affect the natural skin surface pH value. Optimum surface pH is important for the proper functioning of human skin. The final chapters of the described the characteristics of the basic biophysical parameters of the skin (hydration, TEWL, pH, sebum) and methods for their measurement. Key words: skin, transepidermal water loss, pH, hydration, sebum, microbiome
218

Dostupnost zdravotně nezávadné vody v Nikaragui se zaměřením na rurální oblasti regionu Carazo

Křížová, Diana January 2019 (has links)
The diploma thesis deals with the issue of drinking water scarcity in Nicaragua, especially in the rural areas of the Carazo region. Theoretical part describes drinking water definition and the most common causes of problematic accessibility of drinking water including the impacts on local inhabitants. Recommended world water strategies for sustainable water management in developing countries are mentioned. The thesis defines contemporary infectious diseases (infectious diarrhea, viral hepatitis A, leptospirosis, Salmonella typhi, Salmonella paratyphi, cryptosporidiosis, and geohelminth infections) in Nicaragua, and the negative influence on its population's quality of live. Analytical part includes data such as accessibility of drinking water and sanitations. The data were accessed during the stay in Nicaragua, mainly in the Carazo region (62 communities, 8,000 households, 45,024 inhabitants), and also from databases and publications about the selected infectious diseases in Nicaragua. Infectious diarrhea, leptospirosis, and viral hepatitis A are the gravest infectious diseases for the local inhabitants (especially for children). Drinking water is absolutely accessible only in 40 (64.5 %) communities with the population of 36,446 (81.0 %) to all households. Sanitations are absolutely accessible only in 3 (4.8 %) with the population of 14,129 (31.4 %) to all households. This infrastructure does not create suitable conditions for these infectious diseases prevention.
219

Využití elektromigračních metod ke stanovení těžkých kovů v odpadních vodách

Ondračka, Tomáš January 2019 (has links)
The diploma thesis deals with the determination of selected heavy metals in wastewater, while the first part describes electromigration methods and individual heavy metals. In the next part of the thesis is describe, the problems of sewage sludge and methods commonly used for determination of heavy metals in wastewater. The practical part of the thesis describes the development of the electrolyte system together with the use of computer technology. Following is a discussion of the possibility of removing heavy metals from wastewater. In conclusion, the results of heavy metal measurements, comparison with foreign literature and assessment of suitability of the method for analysis of hazardous substances at low concentrations in the environment are presented and commented.
220

Influence of air humidity, air and soil temperature and soil moisture on diameter increment of Pinus spp.

Bartoš, Radek January 2018 (has links)
Increments of hourly intervals of Pinus oocarpa was measured during the year 2015. The research was based in Villa Rica area, Peru. Each hour change of stem was measured by band dendrometer even climatic values like air temperature, air humidity, soil temperature and soil water availability were measured every hour too. The measured tree is part of agroforestry system of coffee, where shading tree is the main role. Measured climatic values were compared to daily changes and weekly changes of the stem. A statistically significant effect (p<0.001) was found only for the temperature and humidity of the air and their effect on changes in the strain during day and night. The above graphs have a clear effect on other values where statistical significance has not been demonstrated.

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