National Repository of Grey Literature 280 records found  previous11 - 20nextend  jump to record: Search took 0.01 seconds. 
Musk compounds in water biota
Zouhar, Libor ; Stoupalová, Michaela (referee) ; Vávrová, Milada (advisor)
Synthetic musk compounds (MUSK) or synthetic fragrances are organic substances commonly used as fragrant constituents of perfumes, detergents, cosmetics and personal care products. These compounds are discharged after use via domestic wastewater and sewage treatment plants to the aquatic environment. The result is accumulation in the environment and occurrence in a food chain especially of aquatic and marine ecosystems. Synthetic musk compounds are also found in surface water, fish tissues and also in body fluid (blood, urine, milk) and tissues of human body. Quantitative detection and studying properties of these compounds is an important activity because we have low knowledge about their fate in the environment (persistence, bioaccumulation) and toxicity. This diploma thesis is focused on three commonly used synthetic fragrances – tonalide, musk ketone and musk xylene. The base of this study was to perform a method optimisation for the determination of selected compounds in water and water biota (fish). The aim was determination of selected musk compounds in real samples (water, fish) and evaluation of the results. Pressurized solvent extraction (PSE) for fish samples and solid phase microextraction (SPME) for water samples were used for isolation of analytes from samples. The identification and quantification of analytes was carried out by high resolution gas chromatography – mass spectrometry.
Communication Strategy for Firm Chytej.cz
Měřička, Radim ; Mráček, Pavel (referee) ; Mráček, Pavel (referee) ; Šimberová, Iveta (advisor)
The thesis deals with potentialities of a company, whose activities are focused in the intrnet environment. Together with maintaining a fisherman portal, the company is involved in producing instructional and narrative movies with fishing themes. In the thesis, different ways to approach special interest groups are discussed, as well as different means of advertising services to these groups. The thesis concludes in several proposals, that may result in the company growth.
Determination of musk compounds in biotic matrices
Soukupová, Alena ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
This diploma thesis deals with actual issues of the contamination in the environment with synthetic fragrances. Musk compounds are infiltrated to many environmental components (especially an aquatic ecosystem) because of their biological persistence and the ability of accumulation. This diploma thesis is focused on the selection and the optimization of method for the determination of musk compounds in real biotic matrices (fish). The isolation of analytes was realized by PSE method and the purification of extract was realized by the method of the adsorption column chromatography. Identification and quantification of individual musk compounds was carried out by GC-MS. In conclusion were results and the contamination of fish from the river Svratka disscissed and evaluated. These fish were caught at the inflow and at the outflow of the wastewater treatment plant.
Cryptids
Dvořáková, Dana ; Turek, Filip (referee) ; Sterec, Pavel (advisor)
Cryptids, video which is studying animals, its shapes, moves and the environment , where they find themselves. The video is looking equal to all entity without any difference, document varied life as same as passing death or rot as well. It also speaks about collaboration and the microworld, which creates perfect unit. Silent mutual conversations.
The evaluation of findings of PCBs in bioindicators of animal origin - fish
Doušová, Petra ; Zlámalová Gargošová, Helena (referee) ; Vávrová, Milada (advisor)
The baccalaureate theoretical thesis resolved the issues of use of fish as bioindicators to determine the level of ecosystem pollution. Polychlorinated biphenyls (PCB) were selected as a xenobiotic; it still belongs among the priority organic pollutants. The part of thesis is dedicated to physical and chemical toxicological and environmental characteristics of these organic pollutants. Its use in CR in the past was also mentioned, as well as manner of its application in industry, evaluation of its distribution and toxicological effect of individual groups of congeners PCB. Based on the contamination level of fish the evaluation of the water ecosystem was performed, which was compared to data published in Slovakia.
Evaluation of occurence of musk compounds in water ecosystem
Tobková, Lenka ; Zouhar, Libor (referee) ; Vávrová, Milada (advisor)
This bachelor’s thesis is concerned with synthetic musk compounds and their presence in the environment, particularly in water ecosystem. The thesis contains fundamental classification of synthetic musk compounds together with specification and detailed description of their most significant representatives. Among them are linalool, citronellol, and isobornyle acetate which will be studied further in master’s thesis. Fundamental physical-chemical properties of these odoriferous compounds and their toxicological and environmental impact are studied. Also part of this thesis is a detailed description of synthetic musk compounds’ analytical determination.
Monitoring of mercury and methylmercury content in fish meat and evaluation of risks associated with the consumption of this meat
Křížová, Lucie ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
Mercury and its compounds are one of the most toxic global pollutants in the environment. It occurs in all segments of the environment, and it attains the food chain ang human body by people consuming fish. The theoretical part of this thesis examines the characteristics of mercury, its occurrence, the roots of its pollution, and the toxicity of various forms of mercury. Consequently, the thesis delineates analytical methodologies applied to determine the overall level of mercury and chemical forms of mercury. The practical part focuses on monitoring the level of mercury and methylmercury in 12 extracts of fish meat. The analyzer AMA 254 has been used to determine the level of mercury and methylmercury in these extracts. Based on the level that resulted from the measurements, the thesis concludes a risk that correlates with consuming this type of meat.
Revitalization of rivers on the way fish-passing facility building
Banzetová, Diana ; Princ, Michal (referee) ; Milerski, Rudolf (advisor)
The bachelor thesis is consisted of two parts. First part is about causes of fish migration and revitalization of streams by building of fish ladders over migration barriers. There are described two basic types of fish ladders, natural and technical including main features. Further it is about design, parameters and check of function of fish ladders. At the end there is summary of legislation and funding options of construction. The second part is dedicated to specific fish ladder. The fish ladder is situated to weir on the river Jihlava in Cvrcovice village. Bachelor thesis is here dedicated to description of one particular fish ladder based on actual fish stock. In this part there are hydraulic countings and specific data acquired of HEC-RAS program, in which was fish ladder designed and tested in simulated run based on hydraulic conditions.
Report on the mapping of the occurence of the Chinese sleeper (Percottus glenii) in the basin of the Osecký and Voldušský stream at Osek u Rokycan
Muška, Milan ; Tušer, Michal ; Holubová, Michaela
Mapping of the occurrence of Chinese sleeper (Perccottus glenii) was carried out at 15 locations in the Osec and Voldušské creek basins, with the aim of checking as many locations as possible with the potential occurrence of Perccottus glenii.
Study of the limnological components of the ecosytem of Lake Medard in 2022
Peterka, Jiří ; Hejzlar, Josef ; Nedoma, Jiří ; Znachor, Petr ; Seďa, Jaromír ; Vejřík, Lukáš
The report summarizes the results of research into the limnological and biological components of the ecosystem of the newly created Medard post-mining lake. The aim of the presented report is to summarize the results achieved for the year 2022 and recommendations for further monitoring. The year 2022 was the fifth year after the lake was completely filled, when water from the Ohře River was no longer added. Only small tributaries flowed into the lake from its own catchment area, and at the same time, water from the lake drained through seeps, which are apparently drained into the nearby rivers, the Ohře and the Svatava. The lake ecosystem reached the final state of its initial phase in terms of hydrological regime and nutrient load. This condition is characterized by very little water exchange and a low nutrient level with low productivity of plankton communities. There is the development of submerged macrovegetation in littoral zone and a specific seasonal change in chemistry and biological parameters. However, the aquatic ecosystem is still far from stabilized and the biological communities of the littoral zone (littoral) and open water (pelagial), including the fish community, still show significant interannual dynamics.

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