National Repository of Grey Literature 210 records found  previous11 - 20nextend  jump to record: Search took 0.00 seconds. 
Study of the content of risk elements in river sediments of the Váh River
Držíková, Klára ; Zlámalová Gargošová, Helena (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the analysis of selected heavy metals in the river sediment of the Váh River. The elements were selected based on their relatively frequent occurrence and adverse effects on humans, fauna, and flora. Also due to their ability of good accumulation and persistence in sediments. The selected elements have a chalcophile character, which plays a significant role in the occurrence of the elements at the sampling sites. The analysis of the collected sediment samples was carried out using atomic absorption spectroscopy. The highest concentration of zinc (386.58 mg/kg), followed by copper (57.67 mg/kg), lead (42.24 mg/kg), and the lowest concentration of mercury (0.332 mg/kg) was measured in the sediments. Sediments are used in agriculture and forestry to improve soil properties. Their application to soils is regulated by Slovak legislation, which sets limit values for risk elements in the concerned sediment and soil. These established limits were not exceeded in any of the sediment samples.
Study of chemical processes initiated by electrical discharge in liquids
Možíšová, Aneta ; Zlámalová Gargošová, Helena (referee) ; Kozáková, Zdenka (advisor)
This Bachelor´s thesis in the first part describes the process of ignition of the plasma discharge in water solutions, the generation of the particles that are generated during the discharge and their subsequent analysis by appropriate analytical methods. The second part focuses on specific cases of the use of the plasma discharge in the environment of selected electrolyte, phosphates were selected for individual experiments and for the comparison of sodium chloride. Phosphates were chosen mainly because of their stable pH as a possible benefit in discharge. The aim is to obtain the most ideal environment for the ignition of the plasma discharge and to optimize the method, which could subsequently be used for medical purposes, especially when sterilizing tools
Determination of nitrates in vegetables by capillary izotachophoresis
Jančová, Nikola ; Zlámalová Gargošová, Helena (referee) ; Řezáčová, Veronika (advisor)
This bachelor thesis deals with determination of nitrates in vegetables employing the capillary isotachophoresis technique. The literature review is devoted to occurrence of nitrates in vegetables, their health risks, the influence of food processing onto nitrate content, commonly used methods of determination as well as the capillary isotachophoresis and its practical application. Experimental part focuses on the application of capillary isotachophoresis for determination of nitrate content in vegetables obtained from conventional agriculture and organic farming.
Evaluation of the effects of biodegradable microplastics on biota of freshwater ecosystem via ecotoxicity tests
Procházková, Petra ; Maršálek,, Blahoslav (referee) ; Beklová, Miroslava (referee) ; Zlámalová Gargošová, Helena (advisor)
Microplastics, which are ubiquitous contaminants of freshwater ecosystems, have raised concerns regarding their potential impact on the environment. For this reason, there is an effort to replace conventional plastics with biodegradable alternatives that can easily degrade in the environment. However, the process of biodegradation of these materials requires specific conditions, such as temperature, humidity, pH, and the presence of microorganisms, which are not always met adequately. Consequently, they may fragment and form biodegradable microplastics that can affect the environment similarly to conventional microplastics. Therefore, the aim of this study was to assess the impact of microplastics of biodegradable poly(3-hydroxybutyrate) microplastics on freshwater organisms, specifically the alga Desmodesmus subspicatus, the plant Lemna minor and the crustacean Daphnia magna. Additionally, we aimed to develop a suitable analytical method for the direct detection of microplastics in the body of D. magna. Although the observed effects were not always significant, they highlighted certain secondary problems that may arise due to the presence of biodegradable microplastics in the environment These issues could be related to biodegradability and the formation of biofilm on the surface of biodegradable microplastics, leading to subsequent nutrient depletion in the surrounding environment. Therefore, the use of biodegradable plastics as a substitute for conventional materials must be approached critically.
Ecotoxicological evaulation samples from burnt-out area
Pasírbková, Adéla ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
In the case of fires frequently wide range of inhomogeneous material is burnt. A lot of combustion products arise during this event, which may adversely affect the environment. Most often detected compounds are carbon dioxide, carbon monoxide, sulfur dioxide, sulphane, hydrogen cyanide, nitrous gases and also organic compounds, which show adverse effects for organism. It is possible to identify and quantify most of them by chemical analysis, but their impact on the ecosystem is not predictable on the basis of these results. An effective tool to predict the impact of combustion products on the ecosystem are ecotoxicity tests. In this thesis, the water leachates of samples from fire places were prepared and subjected to ecotoxicological tests. Two alternative test of ecotoxicity on aquatic organisms were used: the first on the organism Thamnocephalus platyurus (ThamnotoxkitFTM) and the second on the organism Daphnia magna (DaphtoxkitFTM). Another testing aquatic organism was Artemia salina. Ecotoxicity was also tested using a standard phytotoxicity tests; white mustard (Sinapis alba) and white onion (Allium cepa) root growth inhibition tests and lesser duckweed (Lemna minor) growth inhibition test. On the basis of obtained ecotoxicological values LC (EC, IC)50 the impact of matrices from fire places on the ecosystem was evaulated.
Study on the influence of plasma activated water on seed germination
Vozár, Tomáš ; Zlámalová Gargošová, Helena (referee) ; Kozáková, Zdenka (advisor)
This bachelor thesis deals with study on the influence of plasma activated water on wheat seed germination. After interaction with the plasma, the water changes its composition and obtain new properties that are useful in agriculture. The theoretical part is divided into two parts. The first part of the theory is dealing with basic knowledge about plasma, its properties, and possibilities of plasma generation in laboratory conditions. In the second part, the work deals with plasma activated water – PAW. The preparation of plasma activated water is described in details as well as its physical-chemical properties and composition with respect to the PAW possible applications. The aim of the experimental part of this work was to prepare plasma activated water in three different plasma systems and apply it on wheat seeds. These three ways of activation used direct and indirect interaction of plasma with water surface. After the seeds were germinated, the influence of plasma activated water on seed germination and quality of crops was observed and compared to control samples. The influence of different ways of water activation was also evaluated. Results show positive effects of plasma activated water on the seed germination and it also increased the quality of crops. Next steps in this research should be the transfer of this experiment from the laboratory scale on the Petri dish to the pot experiments in soil.
Use of the QuEChERS method for the analysis of fluoroquinolone antibiotics in soil
Brabcová, Kristýna ; Zlámalová Gargošová, Helena (referee) ; Mravcová, Ludmila (advisor)
The content of this master's thesis is an application of frequently used extraction method QuEChERS on soil or other samples like litter or manure containing fluoroquinolone antibiotics. In the theoretical part of this thesis are chapters describing drugs, antibiotics and antibiotic resistance. Fluoroquinolones are described in more details with their properties, appearance and behaviour in the environment. The last chapter is focused on analytical methods. In the experimental part of this thesis is chosen in accordance with available publications the most suitable extraction method. This method is tested and optimized on soil samples. The optimized method is applied on the real soil and poultry litter samples to determine the amount of ciprofloxacine and enrofloxacine. This extraction method is used on other fluoroquinolone antibiotics (norfloxacine, ofloxacine, pefloxacine, moxifloxacine) in soil. All of the samples were analyzed by LC-MS.
Options determination of synthetic fragrances in wastewater
Kašparová, Jarmila ; Zlámalová Gargošová, Helena (referee) ; Vávrová, Milada (advisor)
Synthetic fragrances (musk) are artificially made organic compounds, which are used as fragrances in pharmaceutical and cosmetic products. The presence of musk is proven in all environmental compartments. However, the greatest attention is paid to purified waste water, which is a frequent source of pollution of surface water. The physico-chemical properties of musk compounds cause their accumulation in the living and non-living components of the ecosystem, where they behave as persistent pollutants. The presented bachelor thesis deals with the problem of determining individual musk compounds of all groups side by side. In the bachelor thesis, nineteen musk compounds of four groups, nitromusk compounds, macrocyclic musk compounds, linear musk compounds, polycyclic musk compounds were studied. The basis of this work was to optimize the method for determining all groups of musk compounds side by side, evaluating and interpreting the results. Solid phase microextraction (SPME) was used as a method for extracting analytes. Gas chromatography in conjunction with mass spectrometry was used for the final analysis, as a detector was used for a Time of flight analyzer.
Fish as indicator of aquatic ecosystem´s loading by pharmaceutical residues
Milatová, Martina ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Nowadays, the importance of the issue of residues of pharmacs in the wastewaters and afterwards, surface waters, becomes more serious because of the fact, that the consumption of the pharmacs is instantly increasing within the human population. Therefore, it is important to monitor not only this pharmacs, respectively their residues in waters, but also their residues in aquatic organisms. This thesis is of theoretical character and deals with the possibility of using fish as bioindicators in the evaluation of pharmacs residues in aquatic ecosystems. The examples of farmacs present in the waters are given and the most common of them are described. The synthetic estrogens, whose effects on the aquatic organisms, respectively fish, are most detectable, were chosen as the most common group of pharmacs.
Ecotoxicity of selected musk compounds
Cvikýřová, Zuzana ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Products of daily use, which are mainly cosmetics and personal care products could significantly affect the environment. Recently, in terms of environmental protection, organic compounds responsible for the pleasant smell of these products - synthetic fragrances or musk compounds - are often mentioned. This diploma thesis aims to assess the ecotoxicity of several new substances from the group linear (alicyclic) musk compounds. From this group following fragrance ingrediens were tested: lilial, linalool, arocete and aroflorone. Since the majority of their residues enter the aquatic ecosystem, aquatic freshwater crustacean Daphnia magna and Thamnocephalus platyurus and aquatic plant Lemna minor were selected as test organisms. Individual ecotoxicity of above mentioned substances was evaluated as well as toxicity of binary mixture of arofloron and linalool on organisms Daphnia magna and Thamnocephalus platyurus. Based on the test results the ecotoxicological values LC50, EC50 and IC50 for the tested substances were evaluated and their ecotoxicity was compared. Lilial showed the highest ecotoxicity. Value of 24h EC50 for organism Daphnia magna was 2.13 mg/l and value of 24h LC50 for the organism Thamnocephalus platyurus was 10.86 mg/l.

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