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Analysis of Thick Film Amperometrical Sensors Signal and Its Usage for Measurement and Characterization of Enzymes
Ondruch, Vít ; Kizek, René (referee) ; Masojídek,, Jiří (referee) ; Vrba, Radimír (advisor)
V práci je popsán princip synchronní detekce (SD), který byl uplatněn při měření s biosenzory. Metoda SD umožňuje dosažení výrazně lepšího poměru signálu k šumu, vyššího limitu detekce a celkové zlepšení robustnosti měření. Uplatnění SD při měření s biosenzory umožní zlepšit analýzu jeho odezvy a umožní odstranění nežádoucích interferencí nebo šumů, které mohou být způsobeny například mícháním roztoku, elektromagnetickými vlivy nebo parazitními proudy. SD také umožňuje rozložit získaný signál na odezvu stimulace a na dlouhodobý signál jiného procesu, a dále také identifikovat jevy druhého řádu. Pro identifikaci stimulačního signálu ve výstupním signálu měření byl na základě lineárního statistického modelu vyvinut specializovaný software. SD byla ověřena na modelovém případu výstupního signálu biosenzoru s aplikovaným komplexem fotosystému II (PSII) a jeho odezvě na stimulaci světlem. Odezva PSII se řídí kinetikou prvního řádu a může být také ovlivněna inhibitory. Kinetické konstanty vazby herbicidu na PSII závisí lineárně na koncentraci herbicidu. To umožňuje jejich měření také při nízkých koncentracích herbicidu.
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Possibilities of pesticide degradation by titanium dioxide
Píšťková, Veronika ; Veselý, Michal (referee) ; Vávrová, Milada (advisor)
The aim of this bachelor´s thesis is a selection of pesticides, which could be degradated using titanium dioxide. The first part of the paper deals with general pesticide characteristics, subdivision of pesticides, mode of action on target agents and transformations of pesticides within the environment – the metabolic and the non-metabolic tranformation. The second part of the paper deals with heterogeneous photocatalysis using semiconductor TiO2, which is activated by ultraviolet or solar radiation. Using this method pesticides could be transformed even into carbon dioxide, water and inorganic mineral salts. Furthermore, there are mentioned the factors, which affect degradation rate, analytical methods to determine kinetics of degradation and methods for monitoring transients and end products. By each group of pesticides there are stated the representatives from this group, which have been used for investigation of degradation methods. Furthermore are mentioned decomposition mechanisms of reaction and the intermediate products formed during the photocatalysis process.
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Influence of advanced oxidative processess on ecotoxicity of pesticides
Goma, Bernadette ; Procházková, Petra (referee) ; Zlámalová Gargošová, Helena (advisor)
The topic of this bachelor thesis is a study of the influence of advanced oxidation processes on the ecotoxicity of pesticides Metazachlor and Chloridazon. Both herbicides are commonly used to protect crops such as oilseed rape, turnips, chard or fodder beet against whole range of undesirable monocotyledonous and dicotyledonous plants. Application is most often on large areas and therefore pose a high risk to the quality of the environment. The possible influence on the representatives of producers and consumers of the aquatic ecosystem was monitored in the work. Solutions of pesticides, which were subjected to selected methods of treatment using advanced oxidation processes, were tested on aquatic organisms, specifically on crustaceans Daphnia magna and aquatic plant Lemna minor. From the results of individual tests, the ecotoxicological values of EC50 and IC50 were calculated and their ecotoxicity and thus the efficiency of oxidation processes in the removal of pollutants from wastewater were compared.
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Determination of polar pesticides in waste and surface waters
Borůvková, Tereza ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
This work is focused on the determination of polar pesticides in surface and waste waters. In this study Mecoprop-P, MCPA, Dichlorprop-P, 2,4-D and MCPBA in differently loaded surface waters and communal waters from sewage treatment plants were analyzed. These herbicides are included in the group identified as environmental quality standards. Some of herbicides (2,4-D and MCPA) were selected because their consumption in the Czech Republic exceeds 30 tons a year. Samples were collected prom three rivers near town of Jaroměř (Elbe, Úpa and Metuje Rivers), from one river near the town of Brno (Svratka River) and from inflow and outflow of two sewage treatment plants (WWTP Jaroměř, WWTP Brno – Modřice). Particular rivers were chosen for monitoring due to the probability of occurrence of herbicides, because they flow through agriculturally cultivated areas. Solid phase extraction (SPE) was used for the isolation of target compounds and their concentration. Gas chromatography with tandem mass spectrometry (GC/MS/MS) was used for the determination of target analytes in surface and waste waters. Selected herbicides were detected in all collected samples.
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Multiresidual methods for the determination of pesticides in waters
Matušková, Monika ; Kubíčková, Kristýna (referee) ; Vávrová, Milada (advisor)
This bachelor´s work of theoretical character deals with multiresidual determination of pesticides in water. It is especially focused on pesticides generating residues in surface water, which - due to their toxicity and persistence in environment - require goal-directed monitoring. The division of pesticides is stated, and their properties, toxicity and elimination process are described in the work. Furthermore, possibilities of analytical determination, especially the methods of gas and liquid chromatography are introduced here. In the last chapter, the complete analytic procedure for determination of organochlorine pesticides is described.
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Pesticide glyphosate and possibilities of its determination
Stará, Kristýna ; Mravcová, Ludmila (referee) ; Řezáčová, Veronika (advisor)
This bechelor thesis deals with determination of glyphosate employing capillary isotachophoresis technique. The literature review is devoted to pesticide, their distribution and use, properties and methods for the glyphosate determination, capillary zone isotachophoresis and its use. Experimental part focuses on the application of capillary isotachophoresis for determination of glyphosate, for determination of glyphosate in commercial preparations and testing of glyphosate sorption in soil.
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Detekce příjmu a účinku herbicidů s využitím zobrazovací fluorescence chlorofylu, UV stínění fluorescence chlorofylu a modro-zelené fluorescence
Otáhalík, David
Abstract The diploma thesis is devoted to the problem of detecting the uptake and effect of herbicides using non-destructive methods of chlorophyll fluorescence imaging, UV shielding of chlorophyll fluorescence and blue-green fluorescence on model species of weed plants or plants simulating weed species (cornflower, white mustard) and model species of field crops (spring barley, field peas). Chlorophyll, flavonol, anthocyanin and NBI index were also used for detection, which were measured pointwise. The measurement of the methods took place on the 3rd and 8th day after the application of herbicides. It is clear from the obtained results that the methods used differ in their sensitivity to the action of herbicides with different mechanisms of action, but that their sensitivity also changes over time after application. At the same time, a significant interaction with the species according to its sensitivity to the given herbicide is also evident, but at the same time, some methods have recorded responses to the action of the herbicide even in cases of tolerance to the given herbicide, which may be caused by inducing defensive reactions in the plant, such as the accumulation of flavonols or anthocyanins. 3 days after the application of herbicides, the most statistically significant responses to the action of herbicides were found in the anthocyanin and chlorophyll index, the UV shielding of chlorophyll fluorescence and the current quantum yield of photosystem II (ΦPSII) parameter. On the other hand, the least evident reactions to the action of herbicides were found for the non-photochemical quenching parameter (NPQ) and the flavonol index. 8 days after the application of herbicides, the most statistically significant reactions were found for the blue-green fluorescence index, the chlorophyll index and the ΦPSII parameter. At least for the NPQ parameter and the flavonol index. The chlorophyll imaging parameter ΦPSII, the chlorophyll index and the blue-green fluorescence index, which were measured only on the 8th day after herbicide application, generally achieved the most statistically significant detections of herbicide intake and effect. The methods used thus demonstrate high potential. Detection methods have a high potential in assessing the intake and effect of herbicides, but it is necessary to consider the duration of herbicide action, the sensitivity of the species and possibly also the growth phase during application for own interpretation of the results.
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Využití bezpilotního průzkumu pro cílenou aplikaci herbicidních látek
Panteleev, Evgeny
The thesis "the use of unmanned Exploration for targeted application of herbicides" is focused on the analysis of land data using unmanned Exploration for the following application of herbicides. The theoretical part of the thesis contains a description of common methods for assessing the state of stands in the form of remote sensing. And then it deals with sub-methods, herbicides and drones. The practical part deals with a semi-operational field experiment in the locality of Letkovice. The content includes the results of field and remote sensing, analyzed data from GIS and results of field experiments focused on variable applications of herbicides. And gave an economic comparison of uniform and variable methods of management.
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Vliv chronické expozice chloridazonu a jeho metabolitu chloridazon desphenylu na raka signálního
MATERNA, Jan
The aim of this thesis was to evaluate the effect of chloridazon (Ch) and its major metabolite chloridazon desphenyl (Ch-D) at environmentally relevant concentrations 0.45 micrograms/l (Ch1; Ch-D1) and 2.7 micrograms/l (Ch2; Ch-D2) on adult signal crayfish (Pacifastacus leniusculus). The exposure was 30-day and followed by a 15-day depuration period. The effect of the tested substances was evaluated on the basis of behavior, biochemical profile of hemolymph, biomarker of oxidative stress and antioxidants parameters. The tested substances did not effect on the behavior of crayfish. Chloridazone at concentration 2.7 micrograms/l (Ch2) caused a significant (P<0.01) increase of glucose (GLU), lactate (LACT), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity in haemolymph of crayfish and changes in catalase (CAT) levels in the gills and the hepatopancreas, compared to controls. Crayfish exposed to chloridazon in both tested concentrations (0.45 micrograms/l and 2.7 micrograms/l) showed significantly (P<0.01) higher level of reduced glutathione (GSH) in hepatopancreas and gills compared to control. Exposure of chloridazon desphenyl at concentration 0.45 micrograms/l and 2.7 micrograms/l caused significantly (P<0.01) higher levels of glucose, lactate, ammonia (NH3), calcium (Ca), alanine aminotransferase and aspartate aminotransferase activity in haemolymph of exposed crayfish compared to control. Chloridazon desphenyl in both tested concentrations caused significant (P<0.01) changes in the levels of lipid peroxidation (LPO) in the hepatopancreas and catalase (CAT) and GSH level in the gills and hepatopancreas compared to the control group. Some effects persist after a depuration period. The results showed that the metabolite chloridazon desphenyl has more pronounced effects on the physiology of adult signal crayfish than its parent compound chloridazon. It can be stated, that chloridazon and its metabolite chloridazon desphenyl has the strongly negative and harmful effects of on crayfish as representatives of non-target aquatic organisms.
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