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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.
211

Rtuť v odpadních vodách / Mercury in waste water

Paříková, Lucie January 2008 (has links)
In the time period from November to April of the academic year 2007/2008 presence of mercury and its forms was monitored in the waste waters of Faculty of Chemistry, VUT in Brno. The level of mercury was determined as total mercury with help of the atomic absorption spectrometry method and in available forms by diffusive gradient in thin film technique.
212

Problematika perfluorovaných sloučenin ve složkách životního prostředí / Issues of perfluorinated compounds in the environmental compartments

Kalášek, Stanislav January 2008 (has links)
Perfluoroalkylated substencies are priority organics polutants. They are evolved to the environment from many sources. We classify them as new xenobiotics which are present in the environment. There will be described their chemical, physical and environmental properties in theoretical part and there will be described the analytical chemistry of these substancies in varios types of environmental samples. There will be developed metod for their identification and quantification. For this assignment will be use especially chromathografic methods. There will be developed standard operation procedure. The procedure will be verify on real environmental samples.
213

Analýza degradačních produktů organického barviva po rozkladu v diafragmovém výboji / Analysis of organic dye degradation product after decomposition in diaphragm discharge

Nejezchleb, Martin January 2009 (has links)
The diploma thesis is focused on the identification of degradation products of organic dye Saturn Red L4B resulting by degradation in diaphragm discharge, using separation techniques with mass spectrometric detection.
214

Stanovení alkylderivátů rtuti ve vodním ekosystému / Determination of mercury alkylderivatives in water ecosystem

Doležalová, Jana January 2009 (has links)
Diploma thesis is oriented on the question of the fate and occurence of mercury and its derivatives in water ecosystems. At first, deep literature review will be worked out. At second, the optimal analytical procedure for the determination of mercury alkylderivatives in water ecosystem compartments will be proposed and verified. At third, real samples from selected water ecosystems will be taken and analyzed.
215

Využití separačních metod s hmotnostní detekcí pro studium degradačních produktů nových polymerních materiálů / Application of separation methods with mass spectrometric detection for the study of degradation products of new polymeric materials

Čumová, Martina January 2009 (has links)
Synthetic polymer materials have been a part of human life since the 20th century. A variety of their use had resulted in a growing demand for their mass production, which then led to their increasing accumulation at waste dumps. After their deposition, these materials are exposed to many environmental factors causing their decomposition and subsequent release of the degradation products into the environment. This thesis is focused on the analysis of the photodegradation products from synthetic polymer materials and particularly polyurethane foams modified with the biodegradable fillers. One dimensional GC/MS and two dimensional comprehensive gas chromatography with time-of-flight mass spectrometry (GCxGC/TOF-MS ) were used for the measurements. The most of photodegradation products of polyurethane foams are injurious to health and environment.
216

Stanovení toxických a esenciálních prvků v rostlinných materiálech / Determination of toxic and essential elements in plants

Filipčíková, Marcela January 2009 (has links)
The aim of diploma thesis is occurrence of toxic and essential elements in vegetables and fruit, especially in fruity baby food. The diploma thesis also dedicates processing of vegetables and fruit for production of baby food. Attention is direct to monitoring of baby food quality in the analytical aspects and also to legislative that is in this area. Samples for analysis are prepared using microwave mineralization and ICP-MS for detection. This is described in the experimental part of the diploma thesis.
217

Plazmochemická depozice tenkých fluorocarbonových vrstev / Plasma chemical deposition of thin fluorocarbone films

Veverková, Radka January 2011 (has links)
Deposition of thin films is one of the most widespread applications used for the changes of surface properties of various materials. This diploma thesis is focused on diagnosing of thin film generated by a PECVD technique. The capacitively coupled RF discharge at low pressure was used for the thin films deposition using tetrafluoromethane (CF4) with addition of hydrogen (H2) as a precursor. The aim of the work was the search of optimal conditions for a hydrophobic thin layer preparation on the surface of polymer NOA. The depositions were performed in continuous and pulsed mode with different duty cycle. The discharge was monitored using optical emission spectroscopy and in situ mass spectrometry. Thin films structure and properties were characterized using water contact angle measurements, X-ray photoelectron spectroscopy, infrared spectroscopy and optical ellipsometry. The influence of varying power, gas mixture composition and discharge mode were investigated. Water contact angle was the highest for a deposition in a continuous mode. Decomposition processes inside the reactor were observed by using mass spectrometry and optical emission spektrokopie. X-ray photoelectron spectroscopy provided information about the chemical bonds represented on the surface of sample. These were mainly C – C/C – H, C – O, O = C - O groups for sample without layer. Other chemical bonds were observed after the deposition. These were mainly C – CF, CF2 and CF3 groups. The film thickness of about 8,2 nanometers was measured by optical ellipsometry. The obtained results may be used as a fundament for further more advanced study of plasma chemically prepared thin fluorocarbon films and their properties.
218

Stanovení těžkých kovů v odpadních energetických materiálech s využitím sekvenční extrakce / Determination of heavy metals in waste energetic materials with using sequential extraction

Kořínková, Alena January 2011 (has links)
Tato diplomová práce pojednává o stanovení vybraných kovů v energetických odpadech, jako je úletový popílek, škvára, struska, ložový popel, produkt odsíření apod., které pocházejí ze čtyř moravských tepláren. Extrakce kovů z energetických materiálů byla provedena Tessierovou extrakcí. Za tímto účelem byla použita extrakční činidla chlorid hořečnatý (MgCl2), octan sodný (CH3COONa), hydroxylamin hydrochlorid v kyselině octové (NH2OH.HCl v CH3COOH), peroxid vodíku v kyselině dusičné (H2O2 v HNO3) a kyselina fluorovodíková (HF). Extrakce probíhala při teplotách 25°C a 40°C. Ve všech frakcích byly stanoveny olovo, měď a kadmium s využitím atomové absorpční spektrometrie (F AAS, ET AAS) a rtuť metodou AMA 254.
219

Výskyt těžkých kovů v blízkosti dopravních komunikací v Brně / Presence of heavy metals in vicinity of the roads in Brno

Brzobohatý, Jan January 2011 (has links)
Diploma thesis deals with the risk assessment of metals in soils near roads in the city of Brno. For samples collection has been chosen twenty-five localities which were divided into five groups depending on the traffic load, in order to compare the impact of transport on the risk of soil contamination with metals. In the soil samples were determined levels of six hazardous metals (Cd, Hg, Pb, Zn, Ni, Cu). Lead, zinc, nickel and copper were determined by the flame atomic absorption spectrometry (F-AAS), cadmium by the electrotermic atomic absorption spectrometry (ET-AAS) and mercury by the advanced mercury analyzer AMA 254.
220

Stanovení kovů ve vinné révě pěstované různými způsoby / Determination of selected metals in grapes cultivated by different techniques

Kubicová, Lenka January 2011 (has links)
The aim of this study is to determine the content of selected metals (As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Se, Sn, Sr, Pb, V, Zn) in samples of leaves and grapes produced by ecologic agriculture and compare to results with leaves and grapes produced by integrated agriculture. The measured results used to assess the impact of agricultural technology on the quality of vines and grapes. The amount of elements was analysed using inductively coupled plasma mass spectrometry after previous digestion of sapmles using microwaves. Concentrations of elements in leaves and grapes from organic and integrated farming did not differ significantly only in the case of copper concentrations were measured higher concentrations in samples from organic farming. This difference is probably caused by different doses of authorized protective equipment based on copper in the organic and integrated farming.

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