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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Stanovení organických sloučenin v dehtu / Determination of organic compounds in the tar

Magdechová, Andrea January 2011 (has links)
The diploma thesis deals with determination of organic compounds in the tar. It is focussed on polycyclic aromatic hydrocarbons, BTEX and n-alkanes. The tar samples were collected by Faculty of Mechanical Engineering BUT Brno during two days and under diferent conditions of biomass gasification. The samples were filtrated and refined using column chromatography on silicagel sorbent. Gas chromatography with mass detection was chosen to determine polycyclic aromatic hydrocarbons and gas chromatography with flame ionisation detection was chosen to determine BTEX and n-alkanes.
42

Bisfenol A ve vodním ekosystému / Bisphenol A in water ecosystem

Nohelová, Gabriela January 2014 (has links)
This diploma thesis deals with Bisphenol A, especially with its impact on the aquatic ecosystem. Information about its properties, production and current use are summarized here. Its harmful impact on the environment, especially on the aquatic ecosystem and the human body is characterized. Also the methods of its degradation within the aquatic environment have been described. A summary of the options of a determination of Bisphenol A in water samples is incorporated and the method of gas chromatography with mass spectrometry (GC/TOF MS) and comprehensive two-dimensional gas chromatography with mass spectrometry (GCxGC/TOF-MS) is compared in the experimental part. Analytical determination precedes the isolation of the analyte from the water samples by solid phase extraction (SPE) using SupelcleanTM ENVITM - 18 and derivatization using the silylation reagent, N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). The result of this work is the analysis of a series of real samples from wastewater treatment plants Brno Modřice and Luhačovice by a two-dimensional gas chromatography with mass spectrometry (GCxGC/TOF-MS).
43

Stanovení stability přípravku TauroLock / Determination of TauroLock stability

Matejčíková, Eva January 2018 (has links)
This diploma thesis deals with the study of the anticoagulant and antimicrobial agent TauroLockTM, which is manufactured by the german company TauroPharm GmbH. Based on the background research and taking into account the equipment of analytical laboratories of the Institute of Chemistry and Technology of Environmental Protection, optimal methods of analysis were proposed and a series of experiments were carried out which focused on the determination of the active substance and degradation products of taurolidine in TauroLockTM which was stored for a certain period of time in real conditions. The main task of this work was to determine the presence of taurolidine as the active substance and formaldehyde as the undesirable product of its decomposition.
44

Analýza těkavých organických látek produkovaných monocyty během sepse / Analysis of volatile organic compounds produced by monocytes during sepsis

Bártová, Adéla January 2019 (has links)
This thesis is focused on the possibility of analysis of volatile organic compounds produced by monocytes during sepsis. Method of comprehensive two-dimensional gas chromatography with mass spectrometric detection was chosen for this purpose. Content of the first part was the optimization of the method of two-dimensional gas chromatography for the determination of volatile organic compounds. In this part were gradually adjusted parameters of the gas chromatography method to achieve the maximum efficiency. Further were adjusted conditions of samples preparation. Content of the second part was the usage of already optimized method for the analysis of the samples set of monocytes. Samples were subjected to the action of different inhibitors of the immune system and stimulators simulating bacterial or yeast infection. Based on this analysis were identified some compounds, which are produced by monocytes under condition simulating the infection.
45

Stanovení těžkých polycyklických aromatických uhlovodíků v půdách a sedimentech / Determination of heavy polycyclic aromatic hydrocarbons in soils and sediments

Cáhová, Miroslava January 2008 (has links)
This diploma thesis will be focused on the identification and quantification of PAHs with molecular mass exceeding 278 Da by separation and spectrometric methods available at the laboratories of ICTEP.
46

Sorpce PCP na lignitu / PCP sorption of lignite

Šnédarová, Gabriela January 2008 (has links)
Within the framework of this diploma thesis, the sorptive capability of a lignite as a natural adsorbent was applied on an aqueous solution of pentachlorophenol. The aqueous solution of this substance, which is very dangerous for the environment, was prepared in various concentration ranges according to reached solubility. The solubility is noticed in different literatures variously and then is not applicable. That is why it was necessary to find out the ”real“ solubility. The aqueous solution of pentachlorophenol of given concentration was subsequently put to adsorption with exactly defined quantity of the lignite and as a result the adsorptive isotherms were obtained. These isotherms represent the adsorption capability in dependence on the adsorption duration, quantity of used lignite and concentration of pentachlorophenol solution. By the adsorption with duration longer than one hour, the quantity of adsorbed PCP does not increase markedly.
47

Benzen v benzinech z hlediska ochrany zdraví / Benzene in petroleum-derived products and health protection

Bílková, Karolina January 2008 (has links)
Benzene is very toxic compound, which has carcinogenic and mutagenic effects. Result of these effects is significant reduction of its use and also low hygienic limits in occupational environment and environment. The aim of this diploma thesis was to map out possible exposure to benzene and checking of clasification correctness of motor gasoline and benzine (cleaners, thinners etc.). Determination of benzene was carried out by gas chromatography with flame ionisation detector (GC/FID) and high performance liquid chromatography with diod array detector (HPLC/DAD). Marginally, the diploma thesis was focused on determination of toluene (in june 2007 became effective ordinance no.284/2006 Sb., which forbid to sell products that contain more than 0,1 % of toluene to small consumers). Toluene was determined by same methods as benzene.
48

Stanovení vybraných fytofarmak a jejich metabolitů v odpadních vodách / Determination of selected phytopharmaceuticals and their metabolites in waste waters

Nevědělová, Klára January 2008 (has links)
This diploma thesis will be focused on the identification and quantification of selected phytopharmaceuticals ant theri transformation products using separation and spectrometric methods available in the laboratories of ICTEP.
49

Zhodnocení obsahu PCB a PBDE v rostlinných bioindikátorech / Evaluation of content of PCBs and PBDEs in plant bioindicators

Vondráčková, Ilona January 2009 (has links)
In the assessment of the environment pollution level, bio indicators of vegetable or animal origin are often used. Bio indicators include also needles and moss. The samples of moss and needles taken in different locations in the Czech Republic were examined to find out the presence of xenobiotics of polychlorine biphenyls and polybromide diphenylethers types. Selected analytes have been extracted from the matrix by hexan. Extracts have been refined using column chromatography on mixed florisil/silicagel sorbent. To analysis of selected compounds, GC/ECD method has been chosen. Based on our results a comparison of the contamination level in individual locations was enabled.
50

Syntetické vonné látky ve vodním ekosystému / Musk compounds in water ecosystem

Guryčová, Hana January 2009 (has links)
Synthetic fragrances or MUSK compounds are artificialy synthetised organic substances, used as fragrant constituents in various homecare products, such as cosmetics, detergents, air fresheners etc. The aim of diploma thesis was the quantification of some selected MUSK compounds in the influent and efluent of the water treatment plants.The method of quantification of MUSK compounds in organic matrix was also optimised during the research. Two modifications of solid phase microextraction were tested and evaluated. The analytes were identified and quantified by gas chromatography - mass spectrometry (GC/MS). The results were used to evaluate the amount of MUSK compounds in sewage waters and the ability of various water treatment plants to eliminate this kind of pollution from the water during the treatment process.

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