National Repository of Grey Literature 48 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Optimization of laboratory denitrification test
Novotná, Klára ; Pániková, Kristína (referee) ; Malá, Jitka (advisor)
Leaching from agricultural fields not only releases high concentrations of nitrates into surface and groundwater, but also, for example, pesticides. The aim of this bachelor thesis is to optimize the input nitrate concentration of a laboratory denitrification test. This test will allow the study of the influence of different pesticides on the denitrification process and also the monitoring of their fate during this process. The theoretical part of the thesis describes the nitrogen cycle and its forms, the denitrification process and the factors that influence its progress are discussed in detail. In the practical part, a 28-day laboratory denitrification test was performed. Analytical methods used are described in the thesis as well as the process and the results of the laboratory experiment. Based on chemical oxygen demand profile, N-NOx concentration profile and denitrification rate, an input nitrate concentration of 15 mg.l-1 was recommended.
Comparison of plasma activated water quality prepared by different plasma systems
Staškovanová, Denisa ; Krčma, František (referee) ; Kozáková, Zdenka (advisor)
This diploma thesis deals with generation of reactive species (hydrogen peroxide, nitrates, nitrites) using various plasma systems in distilled and tap water. Prepared plasma activated water differs in the way the plasma is applied, namely plasma above the water surface, plasma inside water or bubbling of plasma gaseous products into water. The main goal is to determine the amount of species produced in different plasma systems and compare them with each other. The effect of ozonizer experimental conditions on the generated amount of reactive species is also monitored.
Characterization of plasma activated water for biomedical applications
Šindelková, Kateřina ; Dzik, Petr (referee) ; Kozáková, Zdenka (advisor)
The aim of this master thesis is to characterize plasma activated water (PAW) prepared in various plasma systems using direct and indirect interaction of plasma with liquid or its surface. Plasma was generated by electric discharges at atmospheric pressure. The prepared plasma-activated water was studied with respect to its use in biomedical applications. The theoretical part deals with plasma activated water. It contains a description of the PAW preparation, its characterization in terms of produced particles or its physico-chemical properties. Also, methods for antimicrobial activity estimation or colorimetric determination of produced particles are described in this section. In the experimental part of this work, the types of discharges that were used for the PAW preparation and their comparison are presented. Two types of liquids were selected for the activation, namely distilled and tap water. Subsequently, concentrations of selected reactive particles in PAW (hydrogen peroxide, nitrates and nitrites) produced in three different plasma systems were determined. Besides the comparison of reactive particles production in various systems, their time stability was studied as well. Over time after the PAW preparation, the values of active particles concentrations have changed due to mutual interactions between the particles. Mainly, nitrites were oxidized to nitrates or vice versa depending on the PAW type and other conditions. Part of the work was also monitoring selected physical properties of PAW, namely pH value and specific conductivity. It has been found that PAW does not retain its activated properties for too long, depending on the type of preparation and methods of storage. Therefore, one of the important goals of this work was to determine and compare suitable storage conditions for PAW with respect to its potential biomedical applications.
Modelling of surface water pollution in Krivoklatsko protected area using GIS
Šereš, Michal ; Matějíček, Luboš (advisor) ; Benešová, Libuše (referee)
Environmental modelling is lately becoming to be one of the most important decision support systems. Hydrological models present significant potential for use especially in area of surface and groundwater protection. In the diploma thesis, the Soil and Water Assessment Tool (SWAT) was used to evaluate nitrate surface water pollution in nine catchments situated in Křivoklátsko protected area during the period of 2003 - 2010. Modelling process consist of assorted consequent steps. First the hydrological model of each catchment was created. Afterwards the sensitivity analysis was conducted to select most sensitive model parameters. Calibration process was carried out after the parameters selection using SWAT-CUP automatic calibration tool. Model results were visualized and evaluated. The results of the model suggested, that the area of interest was not widely endangered by nitrate pollution. Within each catchment the critical source areas of nitrate pollution were identified. It was observed that these areas are related with intensive agricultural areas. Nitrate leaching ranged from 6 kg.ha-1 to 10 kg.ha-1 per year in agriculture areas. Some areas exceed this amount. Nitrate loss from most of the area of interest ranged from 0 kg.ha-1 to 4 kg.ha-1 per year. Concentrations of nitrates in modeled...
Diagnostics of active particles generated by the interaction of plasma microwave discharge with liquids
Kovaříková, Kateřina ; Töröková, Lucie (referee) ; Kozáková, Zdenka (advisor)
The first part of this Bachelor’s thesis describes problems of electric discharges in gas and on a surface of water solutions. It focuses on the generation of the active particles that are generated during the discharge and their subsequent analysis by appropriate analytical methods. The second part focuses on identification of the active particles that are generated during the microwave discharge in gas phase and during the interaction with water solution surface. The aim is to determine the influence of experimental conditions on the information of the active particles, specifically the nitrates and nitrite ions.
Nitrate removal from agricultural runoff
Schrimpelová, Kateřina ; Šálek,, JAN (referee) ; Drtil,, Miloslav (referee) ; Malá, Jitka (advisor)
The increasing concentration of nitrates in surface water and groundwater is becoming a global problem. The dissertation thesis is focused on the denitrifying bioreactors with organic fill material designed for the reduction of nitrate input from agricultural areas in the Czech Republic. A set of laboratory experiments was performed – static leaching tests and column tests, including chemical analyses of outflow water and ecotoxicological bioassays. Seven materials common in the Czech Republic, various process parameters, types and lengths of bioreactor shutdown in dry periods and the use of outflow water for irrigation were tested. The thesis deals with both denitrification efficiency and ways of reducing negative effects. An evaluation of the overall effect bioreactors is included along with a prediction regarding leaching over the following years.
Farming practices for efficient use of nitrogen and reduction of its losses: Certified methodology for practice
Klír, Jan ; Haberle, Jan ; Růžek, Pavel ; Šimon, Tomáš ; Svoboda, Pavel
The methodology describes the main risks of nitrogen losses and recommended practices for their reduction. Practically applicable methods for the evaluation of the nitrate leaching risk depending on the soil, crop, root range, croping system, irrigation and weather conditions are described in detail. Consequently, suitable soil treatments and fertilization are proposed to improve the utilization of the nitrogen and uniformity of the water soaking.
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The influence of agricultural activities on the stream water quality in natural reservation
The aim of this thesis is to evaluate the impact of agricultural activity on hydrochemical parameters of surface waters in connection with the occurence of specially protected species within the surface waters of a monitored area. A model was chosen for the evaluation of the situation - Bedřichovský potok, which is located in Novohradské hory. The river consists of lower and upper sub-waters. Forest management is applied within upper sub-basin, while agricultural management on arable land, meadows and pastures is used in the lower sub-basin. The monitored parameters were indicators of eutrophication of surface waters: Nitrate nitrogen (N-NO3-), Phosphate phosphorus (P-PO43-), and conductivity of undissolved material (NL105). The results showed that the agriculture management (especially on arable land) burdens the soil with nutrients and consequently erosion enters the substances, bringing them to the surface and ground water as a result. There was an increase of substances in the water after rain.
Methodological guidance for management in vulnerable zones: 2nd edition; Certified methodology
Klír, Jan ; Kozlovská, Lada ; Haberle, Jan ; Mühlbachová, Gabriela
The methodology describes measures for protection of waters against pollution caused by nitrates from agricultural sources in vulnerable zones of the Czech Republic. The methodology clearly describes individual requirements of the 4th Action Programme of the Nitrates Directive for the period 2016–2020 as ratified by CR government for reduction of nitrogen losses by nitrates leaching into surface water and groundwater, reduction of surface water eutrophication and reduction of nitrates transmission to the neighboring countries in waters flowing from the territory of the Czech Republic. The aim is to reduce water pollution by nitrogen compounds from agricultural sources into the aquatic environment, the results of which are such as to cause hazards to human health, harm to living resources and to aquatic ecosystems, damage to amenities or interference with other legitimate uses of water. The publication also includes links to selected technical publications and related legislation. The second updated edition responds to amendment to the Government Regulation No. 262/2012 Coll., On determining the vulnerable areas and action programme, issued in 2018 as No. 27/2018 Coll.
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Technologie pěstování a hnojení ječmene (Hordeum) s cílem maximální kvality produktu a jeho využití pro výrobu doplňku stravy "zeleného ječmene".
In this thesis, I focused on the cultivation and fertilization of barley and its use as a food supplement called "green barley". Nowadays people eat unhealthily, they do not diet, their food intake consists of a few essential nutrients and this leads to various illnesses and diseases. Green Barley is one of the ways how to replenish essential nutrients, such as vitamins, minerals, enzymes and others. Its regular use can achieve better physical condition and health and it also prevents from various diseases such as anemia, cancer, heart disease, blood vessels and skin diseases etc. The aim of this study was to figure out the best way of cultivation and fertilization of green barley. One of the best methods is practiced in the US, where green barley is grown on dried-up freshwater lakes where there is a very fertile soil and green barley can grow in ecological way. In the Czech Republic, it is better to cultivate green barley in conventional agriculture environment because the soil is fertile and there is a little need to fertilize it. If green barley in our area grew in ecological way, it would increase the nitrate content in the plant due to nitrogen-potassium fertilizer manure. The plant is not able to convert all the nitrogen in organic substances and redundant nitrogen remains in the plant in the form of nitrates.

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