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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.
11

Umělá sladidla a jejich případný vliv na ekosystém / Artificial sweeteners and their potential impact on the ecosystem

Vavrčíková, Veronika January 2017 (has links)
This diploma thesis deals with the determination and ecotoxicological assessment of artificial sweeteners. The diploma was focused on monitoring the most commonly used sweeteners, which includes acesulfam-K, cyclamate, saccharin and sucralose. These sweeteners were analyzed by liquid chromatography with mass spectrometry, using solid phase extraction for their concentration. The samples for their determination were taken from wastewater treatment plant in Modrice. Artificial sweeteners are synthetically produced substances, which is the main reason for their occurrence in waste water. Some of them are not efficiently removed from the wastewater treatment plant and penetrate into the environment. Analysis of the samples was found, that sucralose penetrates into the environment. The ecotoxicological effect of the sweeteners was evaluated via aquatic organisms, namely on the freshwater crustaceans Thamnocephalus platyurus and Daphnia magna, on the water plant Lemna minor, and the battery of tests was supplemented by a representative of the destructors Vibrio fischeri. For all sweeteners, LC20, EC20 and IC20 values were determined. For some sweeteners, LC50, EC50 and IC50 values were also determined. During testing, saccharin represented the highest toxicity.
12

VYUŽITÍ ALTERNATIVNÍCH TESTŮ BIOTOXICITY PRO STANOVENÍ NEBEZPEČNOSTI STÁVAJÍCÍCH A/NEBO POTENCIÁLNÍCH POLUTANTŮ / UTILIZATION OF ALTERNATIVE TESTS OF BIOTOXICITY FOR DETERMINATION INADVISABILITY OF EXISTING AND/OR POTENTIONAL POLUTANTS

Vašulková, Lucie January 2008 (has links)
This thesis is focused on attestation of ecotoxicity of octachlorstyrene (OCS), persistent organic pollutant (POP), by biological tests of toxicity. The toxicity of OCS was determined by using two kinds of alternative tests applied on fresh water organisms. First of them, Thamnotoxkit, is based on observation of mobility, immobilization or even killing of crustacean Thamnocephalus platyurus. The second one, Daphnotoxkit, applies crustacean Daphnia magna. For purposes of comparison, a standard test of toxicity – so called test of root growth inhibition of Sinapis alba and two fytotests – test of growth inhibition of Lemna minor and test of root growth inhibition of Allium cepa were performed as well.
13

Akumulace těžkých kovů v tkáních bezobratlých živočichů na struskopopílkových odkalištích / Accumulation of heavy metals in tissues of terrestrial arthropods at fly ash deposits

Mengr, Jan January 2017 (has links)
No description available.
14

Akumulace těžkých kovů v tkáních bezobratlých živočichů na struskopopílkových odkalištích / Accumulation of heavy metals in tissues of terrestrial arthropods at fly ash deposits

Mengr, Jan January 2017 (has links)
No description available.
15

Posouzení účinnosti úpravny pitné vody prostřednictvím ekotoxikologických testů a screeningové analýzy / Assessment of the drinking water treatment plant effectiveness via ecotoxicological tests and screening analyses

Nývltová, Barbora January 2017 (has links)
The quality of raw water is deteriorating with the continuous increase in environmental pollution. Raw water is being modified to drinking water by technological processes, and it is therefore necessary to put increased demands on the efficiency of these technological processes and their possible innovation. Due to the fact that raw water is contaminated with different types of pollutants, it is necessary to continuously control the drinking water supplied to the public distribution network in order to ensure its quality. Drinking water treatment is still unable to treat the raw water perfectly, its pollution is only reduced to acceptable standards. For this reason, it is indispensable that the quality of drinking water is being checked regularly and at the same time the efficiency of individual technological processes of drinking water treatment is assessed. This includes screening analysis or eventually ecotoxicological tests. The thesis focuses on the efficiency of technological processes of drinking water treatment. Within the experimental part, samples of raw water and samples of water after each separation stage have been collected at the drinking water treatment plant in the Czech Republic. These samples have been subjected to ecotoxicological tests and screening analysis. Based on the ecotoxicological tests carried out on Thamnocephalus platyurus, Lemna minor and Vibrio fischeri, we can assume the emergence of harmful chlorinated by-products, resulting to nearly 100% mortality in T. platyurus. The results of the screening analysis carried out indicate, after the extraction of specimens by the SPE method using HPLC/MS, that the most effective method for the removal of hormonal substances is ozonization.
16

Ekotoxikologické hodnocení polymerů a biologicky aktivních látek v akvatickém prostředí / Ecotoxicological Evaluation of Polymers and Biologically Active Substances in Aquatic Environments

Kašpar, Otakar January 2015 (has links)
To determine the ecotoxicity of analgetics, first the individual ecotoxicity values of individual analgetics are determined and then a mixture of two analgetics is tested. To determine the toxicity, both standard and alternative toxicity tests are used (daphnia magna, sinapsis alba, scenedesmus subspicatum, vibrio fischeri, thamnotoxkit FTM a daphnotoxkit FTM magna). The analgetics being whish tested are the commonly used medicines ibuprofen, ASA, diclofenac and paracetamol, which are the most frequently used medicines in the Czech Republic and whole Europe. To determine the ecotoxicity of the polymers, I‘m using an indirect method of examination, in which I determine the antagonistic or synergistic effects of the mixture of monomers from which the polymer is prepared and into which it slowly decomposes in nature. For the determination both standard and alternative toxicity tests are used. The polymers the toxicity of which is being determined are the habitually used polymer PET and the formaldehyde resine known as bakelite in Eastern Europe.

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