National Repository of Grey Literature 21 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
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.
Monitoring of selected metals in comercial bio wines
Bortlová, Alžběta ; Reichstädter, Marek (referee) ; Pořízka, Jaromír (advisor)
This bachelor thesis is focused on monitoring of selected metals in commercial organic wines. The aim of this thesis was to compare element content of organically produced wines with wines originating from other agrotechnical production system. Optical emission spectrometry with inductively coupled plasma (ICP-OES) was used for element analysis of wine. Statistical method analysis of variance has been used to assess whether the concentrations of the elements showed statistical differences between wines originating from organic production and wines originating from other production systems. Statistical differences were found in 3 of 20 analysed elements. Correlations between the element analysis and type of production system of grapevine were observed in content of the zinc, nickel and manganese.
Determination of residues of the selected pesticide effective substances in wine using the GC/MS method
Ehrenbergerová, Martina ; Benešová, Karolína (referee) ; Mikulíková, Renata (advisor)
The grape is one of the oldest cultivated plants. It can be consumed as a fruit or it can be used as a raw material for making stews, juices or the cultivated drink – wine. Generations of wine-makers have been striving to improve both the cultivating conditions of vineyards and the quality of wine. Many harmful elements, such as herbivorous pests, diseases and storms are important factors that can have a negative impact on crop quality. To regulate the effects of these factors, an integrated protection system is used, incorporating agronomical measures, resistant varieties and a wide spectrum of pesticides. However, increasing the usage of pesticides brings certain dangers to both the production quality and the environment. This necessitates the monitoring of the negative effects, including the content of pesticide residues in the grapes. My thesis studies and experimentally assesses selected pesticide residues in certain wine samples.
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.
Multirezidual analysis of selected pesticides in barley
Ehrenbergerová, Martina ; Duroňová, Kateřina (referee) ; Mikulíková, Renata (advisor)
Barley is one of the economically important crops. Its production is primarilly used as fodder barley and also in brewery and food industry. Particularly the part of its production intended for malt production must be of high quality. There are some important factors which can influence the quality of the crops, such as harmful organisms – diseases, pests and weed. In order to regulate the occurence of harmful organisms, agricultural measures are taken in the integrated protection system and resistant variants and pesticides are used. The higher the demand on the production quality, the bigger is the volume and the spectrum of pesticides used. The increasing extent of pesticide use also poses a risk for internal production quality and the environment. This fact makes it necessary to monitor unfavourable influences, including the contents of the pesticide residues in barley. This work studies the possibility of multiresidual determination of some selected pesticides in malting barley.
Výskyt patogenů a škůdců v porostu máku setého
Gabčíková, Rebeka
This work in its theoretical part deals with the basic characteristics of oilseed poppy cultivation, with a focus on the characterization of pests and diseases. The practical part of the work was conducted in the form of an experiment, which was carried out on the land of the company Agroregión a.s., based in Rajec, Slovakia. The experiment consisted of monitoring pests and diseases and evaluating the abundance of their occurrence in different variants of chemical treatment (control, insecticide, insecticide + fungicide). The occurrence of the black bean aphid (Aphid fabae) was detected among the pests, for which the direct impact of insecticidal treatment on the abundance could not be demonstrated. The occurrence of poppy downy mildew (Peronospora arborescens) was confirmed among the diseases, and the results in the form of the percentage of affected plants proved to be an insufficient measure for the evaluation of the disease progress. However, from the attached photographs, it is apparent that fungicidal protection in this case provided significantly better plant health.
Monitoring of inorganic contaminants in moravian white wines
Šebek, Richard ; Slavíková, Zuzana (referee) ; Pořízka, Jaromír (advisor)
This bachelor thesis is focused on monitoring of selected inorganic contaminants, especially metallic elements and macro elements, in Moravian white wines. The aim of this thesis is to compare the element composition of wines according to the geographical origin, different production system and vine varieties. Two spectrometric techniques were used for elemental analysis of wine samples: Inductively coupled plasma with mass spectrometer and inductively coupled plasma with optical spectrometer (ICP–MS and ICP–OES). Evaluation of the results was carried out using statistical method of variance analysis (ANOVA). Vanadium, copper, lead and magnesium were evaluated as statistically significant in at least one Moravian sub-region. No statistically significant results were found in other comparisons.
Vyhodnocení účinku stromové injektáže u vybraných houbových patogenů u borovice černé (Pinus nigra J. F. Arnold)
Buben, František
This diploma thesis deals with fungal pathogen Sphaeropsis sapinea, which extends massively mainly to the Austrian pine (Pinus nigra). Dieback and die of Austrian pine are caused cooperation between stress and Diplodia blight. Thesis summarized the knowledge of the effects and influence of this pathogen on trees, monitors the possibilities of defence and protection, finding a fungicide in the laboratory, which would effectively reduce damage by injection into mature trees, subsequently. Nine commercially available fungicides were tested in laboratory conditions. Topas 100 EC (effective substance penconazole), Propizol 250 EC (effective substance propiconazole), Dithane DG Neotec (effective substance mancozeb) and Horizon 250 EW (effective substance tebuconazole) had impact for limitation of grow of mycelium S. sapinea. Horizon 250 EW (effective substance tebuconazole) has the highest effectivity in laboratory testing. However, the field testing did not prove its very good properties from laboratory testing.
Analytical approaches to study group interactions of azole pesticides with important biological active compounds
Kovač, Ishak ; Jaklová Dytrtová, Jana (advisor) ; Száková, Jiřina (referee) ; Navrátil, Tomáš (referee)
This dissertation presents a developed capillary electrophoresis method for analysing residues of triazole fungicides (TAF) from real samples ("Sweet cherry" tomato - Solanum lycopersicum L) and shows its potential application in environmental analysis. The developed method was validated in-house and characterised by a relatively short analysis time and low cost with sufficient LOD and LOQ. As an additional part of this dissertation, which rose from the tomato plants' treatment with TAF, we studied the impact of triazole fungicides on plant development and their impact on biologically active compounds. Determination of TAF residues from tomato peel carried out with capillary electrophoresis. Capillary electrophoresis is a versatile technique with minute amounts of sample required, with high efficiency in separating small molecules, such as selected TAF. The developed method, cyclodextrin-modified micellar electrokinetic chromatography, accomplished a baseline separation of the TAF mixture from tomato peel. The optimal conditions for separation were in the background electrolyte comprised of phosphoric acid and Tris (100 mM concentration, respectively), 20% v/v methanol, with apparent p[H+ ] 4.8. The constituents of the mixed micellar pseudo-stationary phase were ionic detergent sodium dodecyl...
Azole resistance in Aspergillus fumigatus: genetic background and mechanisms of spread in the Czech Republic
Holíková, Kristýna ; Hubka, Vít (advisor) ; Chrenková, Vanda (referee)
Aspergillus fumigatus is a widespread saprophytic fungus. As an opportunistic pathogen it can also cause aspergillosis, which can manifest itself as a life-threatening infection in immunocompromised patients. Azole derivatives constitute first-line therapy of aspergillosis, but the increase worldwide of azole-resistant A. fumigatus strains represents a serious clinical problem. So far most of the molecular mechanisms causing azole resistance are dependent on the cyp51A gene. Studies of the last decade have shown that primarily because of the use of azole fungicides in agriculture, azole-resistant strains of A. fumigatus are selected in the environment. This subsequently complicates the treatment of patients with aspergillosis, and the incidence of infections unresponsive to treatment with azole antifungals increases. Increasing incidence of azole antifungals-resistant infections has become a growing concern: yet the prevalence of azole resistance has not yet been assessed in Czech Republic. Therefore, the first objective of this thesis was to determine Czech Republic's prevalence of azole resistance in clinical strains of A. fumigatus. Those findings permitted the observation of the molecular-genetic mechanisms of this resistance. Second aim was to study environmental prevalence of azole resistance...

National Repository of Grey Literature : 21 records found   1 - 10nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.