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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.
221

Necílený screening organických polutantů ve vodách a sedimentech / Non-target screening of organic pollutants in waters and sediments

Hamalčíková, Veronika January 2011 (has links)
This master thesis deals with the potential influence of the waste dump Hrádek u Pacova and the wastewater treatment plant Brno – Modřice on surroundings using the optimized non-target screening method of organic pollutants in water and sediments. The experimental part is focused on the identification of organic compounds in samples of ground water from monitoring wells, the surface water from stream and pond and in sediment samples collected from streams in the vicinity of municipal waste dump. Organic compounds were also identified in water and sediment samples from the river Svratka near the municipal waste water treatment plant Modřice. The sequential liquid – liquid extraction was used for the isolation of organic compounds in water samples. Organic compounds in sediment samples were isolated by pressurized solvent extraction (PSE) with subsequent fractionation of the extract using column chromatography. Final analysis determination was performed using comprehensive orthogonal two-dimensional gas chromatography with mass spectrometric detection (GCxGC-TOF MS).
222

Využití včelího pylu jako bioindikátoru stavu životního prostředí / The application of pollen as bioindicator of the environmental state

Marečková, Kateřina January 2011 (has links)
Pesticides and their excessive use lead to environmental pollution. Violation of the guidelines for their use disposal of empty containers could lead to contamination of water, soil and poisoning of animals and beneficial insects. Honey bee is useful creature on our planet. Good farming depends entirely on the pollination, but whole vegetal kingdom couldn’t exist it form known and used by mankind. Therefore, rules that protect these useful creatures against inadequate use of pesticides have been developed. This study focuses on the evaluation of the possibility to use bee products as bioindicators of the state of environment. Five active substances which are components of pesticides used in the treatment of agricultural field around Tasovice village were analysed in the pollen and honey. For sample preparation QuEChERS and SPE methods were used, gas chromatography with to mass spectrometric detection was employed as final analytical technique.
223

Korozní degradace hořčíkových slitin v SBF roztocích / Corrosion degradation of magnesium alloys in SBF solutions

Ročňáková, Ivana January 2012 (has links)
Nowadays, magnesium alloys are used in many sectors of human activity, particularly in the aerospace and automotive industries, due to a combination of good mechanical properties and low density of magnesium. Recently, however, the attention is paid to the possibility of using magnesium alloys in the medical field, mainly due to the chemical properties of magnesium. The diploma thesis is focused on evaluating of the corrosion behavior of AZ31alloy and AZ61 alloys in SBF solutions that are solutions simulating body fluids. The alloys were subjected to immersion test in Hank’s solutions for time span from 24 to 1008 hours. The corrosion process was evaluated based on several factors: alloy composition, time and pH changes. The thesis also describes in detail the methodology for establishing magnesium and zinc by method of flame absorption spektrometry (F AAS). The determination of aluminum was carried out by atomic absorption spectrometry with electrothermal atomization (ET AAS).
224

Obsah adaptogenů v rostlině Schizandra chinensis / Content of adaptogens in vegetable Schizandra chinensis

Kozáková, Soňa January 2013 (has links)
This thesis deals with the content of adaptogens in vegetable Schizandra chinensis. The theoretical part deals with the plant Schisandra chinensis, its occurrence, characteristics, uses and cultivation. Location of plants Schisandra chinensis are classified according to Köppen climate classification and compared with the climate in the Czech Republic, due to possible prediction of growing plants in the country. Further are described adaptogens (bioactive substances) contained in this plant and to methods for their extraction and analysis. The experimental part of the thesis deals with the identification of schisandrin in the plant Schisandra chinensis grown in our conditions. The assessment was performed by ultra-performance liquid chromatography (UPLC), high-performance liquid chromatography (HPLC) and direct injection into tha mass spectrometry (MS). Schisandrin was successfully identified in all the samples.
225

Využití přístroje GDA-2 v praktické činnosti jednotek Hasičského záchranného sboru / Application of GDA-2 instrument in practical activities of Fire Rescue Units

Rousková, Renata January 2014 (has links)
This diploma thesis is aimed at the use of mobile analyzer Gas Detector Array GDA 2 by Fire Brigade Units of the Czech Republic. The goal of the theoretical part was to get acquainted with this instrument and with the possibilities of its use, to describe the principle of analytical methods used in this analyzer. The experimental part was aimed on the analyses of toxic gases and vapors in the air and on the comparison of obtained result. Final part of diploma thesis evaluates the contribution of mobile analyzer GDA 2 for rapid identification of unknown toxic compounds by Fire Brigade Units of the Czech Republic.
226

Stanovení lineárních syntetických vonných látek v abiotických a biotických matricích / Determination of linear synthetic aromatic compounds in abiotic and biotic matrices

Tulková, Tereza January 2014 (has links)
Synthetic musk compounds are artificial organic compounds with a smell similar to the odor of a natural musk. The most recently discovered and also the least known group of artificial musks is linear musk compounds. These substances are now often used in cosmetics, personal care products, detergents and various cleaning products. They have leaked into all the major environment components, especially into the hydrosphere. There has been great attention drawn to synthetic musk compounds in the last few years because of their environmental impact. The aim of this thesis is to identify twelve linear musk compounds (linalool, 2-cyclohexylethanol, fresco menthe, citronellol, HSA, isobornyl acetate, arocet, aroflorone, allyl cyclohexyl propionate, lilial, isoamyl salicylate and hexylcinnamic aldehyde) in waste water samples. The samples were taken at three different waste water treatment plants (WWTP) in South Moravian region (WWTP Brno-Modřice, WWTP Luhačovice and WWTP Hodonín). Each of these treatment plants has a different equivalent number of inhabitants. At first, a working method was optimized, then applied on real waste water samples. Solid-phase microextraction (SPME) technique was used for the extraction of analytes. Gas chromatography–mass spectrometry (GC/MS) was then used for identification and quantificaton of the studied compounds.
227

Stanovení obsahu platiny na území města Brna / Determination of platinum in Brno's agglomeration

Dvořák, Rostislav January 2014 (has links)
This thesis is focused on the determination of platinum in samples of road dust and soil by atomic absorption spectrometry. The theoretical part describes the basic physical and chemical properties of platinum, platinum function in automotive converters and its behavior in the environment. In the experimental section summarizes the methods used to decompositions samples, concentration of the analyte and the main results of the measurements.
228

Stanovení organických sloučenin v dehtu po spalování a zplyňování biomasy / Determination of organic substances in tar formed after biomass combustion and gasification

Hájek, Radek January 2015 (has links)
Biomass pyrolysis and gasification techniques count among basic technological procedures for its use as a source of energy. As a side-effect, production of tar can be considered. Tar is a complex mixture of various organic compounds and affects negatively both the environment and the facilities where biomass is processed. Within the scope of this master thesis the analysis of tar samples from different materials was performed. As an appropriate analytical method the gas chromatography combined with flame ionization detection (GC-FID) and time-of-flight mass spectrometry (GC-TOF-MS) was chosen. The concentrations of volatile organic compounds known as BTEX, polycyclic aromatic hydrocarbons (PAH) and phenolic compounds were assessed.
229

Studium vlivu požárů skládek komunálních a průmyslových odpadů na kontaminaci životního prostředí, produkty hoření pryže a halogenovaných polymerů / Study of the influence of fires of municipal and industrial waste landfills on the enviromental contamination, the combustion products of rubber and halogenated polymers

Sikora, Henryk January 2014 (has links)
This thesis deals with the issue of fires of municipal and industrial wastes, particularly of rubber and halogenated polymers. When these materials burn, significant amount of harmful substances liberate into environmental compartments. Analysis of samples subjected to thermal decomposition in laboratory conditions explored formation of characteristic compounds in dependence on conditions of combustion. Samples of air, water and soil taken from real fires that occurred between the years 2007 – 2011 in the region of Western Bohemia monitored spreading of these substances into the environment. Majority of these samples were analysed by the means of gas chromatography with mass spectrometric detection. Additionally the effect of extinguishing methods and use of fire extinguishers on formation and spreading of combustion products was studied, especially in soil and in water sources.
230

Detekce zbytkové vlhkosti pórovitého prostředí metodou elektrické impedanční spektrometrie / Detection of residual moisture of porous media using electrical impedance spectrometry

Műnsterová, Zuzana January 2016 (has links)
Diploma thesis examines detection of residual moisture of porous media of using the measuring apparatus based on the application of the method of electrical impedance spectrometry (EIS). The devices Z-meter of third and fourth generation, were used for measurement, which were designed in projects international applied research. Experiment was executed in Laboratory of Water Management Research, Faculty of Civil Engineering, Brno University of Technology.

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