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The use of ion exchanges for preconcentration of platinum group metals
Sýkora, Jiří ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
The aim of this thesis is the elaboration of a detailed literature review on the use of ion exchangers for the preconcentration of platinum group metals. This work contains an actual literature review on this issue. In this work you will find information about the current occurrence of platinum metals in the environment, their impact on health, properties, resources and the use. There are also described ways of decomposition, extraction and use of ion exchangers. In the experimental part this thesis deals with optimization of ion exchangers and following application of real samples from the city of Brno.
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Increasing of the efficiency of electrochemical generation of volatile form of cadmium for trace analysis using AAS
Růžková, Pavla ; Rychlovský, Petr (advisor) ; Červený, Václav (referee)
The aim of the diploma thesis was an improvement of the efficiency of electrochemical generation of volatile form of cadmium used in atomic spectrometric methods. The increase of the efficiency of electrochemical generation of volatile form results in overall improvement of the sensitivity of measurement and therefore, it is possible to achieve lower values of detection limits and limits of determination. One of all the possibilities for improving of overall efficiency is a minimization of loss of volatile form of Cd during transport. Another essential possibility is coupling of the technique of electrochemical generation of volatile form of Cd with in-situ collection (and atomization) in graphite furnace of atomic absorption spectrometer. Keywords: Atomic absorption spectrometry, electrochemical generation of volatile compounds, generation efficiency, electrolytic flow-through generation cell, quartz-tube atomizer, graphite furnace, in-situ trapping, cadmium
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Platinum group elements in waste and surface waters
Novotný, Matěj ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This assignment provides a detailed description of platinum metals, their occurrence in surface and waste water and their determination options. Currently, platinum metals are widely used in the automotive industry as a part of a catalyst, as well as in medicine and jewelery. Release of these metals in pure form and the form of oxides leads to their subsequent accumulation, which directly affects fauna and flora. Due to that, the living conditions and health status of some organisms are petting worse.
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Microdetermination of cobalt by methods of molecular and atomic absorption spectrometry
Charuza, Martin ; Řezáčová, Veronika (referee) ; Sommer, Lumír (advisor)
This diploma thesis is focused on microdetermination of cobalt by UV-VIS spectrophotometry with organic agents and comparison with atomic absorption spectrometry. In the first part properties, occurance and importance of cobalt in the environment are desribed, complete with as a part of vitamine B12. Attention is also given to cobalt compounds, especially in the oxidative states +II and +III. Methods of preconcentration and preparation cobalt determination in real samples are adduced. In this thesis are described some optical analytical methods with accept on spectrophotometric agents for determination of cobalt. The experimental part of this thesis icludes optimalization of the spectrophotometric determination of cobalt with choosen organic agents 4-(2-pyridylazo)resorcin and 2-(5-Brom-2-pyridylazo)-5-diethylaminophenol and optimalization of atomic absorption spectrometry for cobalt determination. All of real samples of water (surface, underground, mineral and waste) were measured by both 4-(2-pyridylazo)resorcin and 2-(5-Brom-2-pyridylazo)-5-diethylaminophenol via UV-VIS and via atomic absorption spectrometry. Results of determinations were compared. A sample of vitamine B12 was measured too by all techniques.
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Bioavailability of metals species in water ecosystem
Tandler, Ágnes ; Řezáčová, Veronika (referee) ; Vávrová, Milada (advisor)
Koncentrace volných kovových iontů je často jen malou částí celkové koncentrace kovu v prostředí. Přes tento malý obsah, je ve většině případů koncentrace volných kovových iontů klíčovým faktorem při určování biodostupnosti a toxicity pro organizmus. Membránová technika Donnan se používá k měření koncentrace volných kovových iontů a v této diplomové práci je ověřena pro směsi kovů (Pb + Cu) při absenci a přítomnosti malých organických ligandů. Olovo a měď jsou environmentálně důležité kovy díky své toxicitě a rozdílným vazebným vlastnostem ve vztahu ke studovaným ligandům.
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Representation of selected elements in human hair
Jochimová, Eva ; Janoušková, Eva (referee) ; Zemanová, Jana (advisor)
Hair is an excellent matrix for monitoring trace elements and minerals in the body. To long-term changes in concentration of elements in the body are reflected in their value in her hair, so the assessment of the organism from the mineral analysis of hair is a very suitable method. This method is widely used in toxicological testing and forensics. This work deals with the analysis of Mg, K, Fe, Zn, Mn, Se, As, Cd and Pb in 100 samples by ICP-MS. It is a male hair samples with the age range 19 – 74 years. Analysis of hair revealed that concentrations of individual elements are moving in a narrow range of values. Values of older age category are in some case significantly deflective.
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Study of metals bioaccumulation by the aquatic moss Fontinalis antipyretica
Jaskowiecová, Lenka ; Hekera,, Petr (referee) ; Diviš, Pavel (advisor)
This diploma thesis is focused on determination of bioavailable cadmium in natural waters. Thesis is devided to two parts-laboratory study in model solution and experiments in real surface water system. During the laboratory experiments the accumulation and release constants of cadmium by aquatic moss Fontinalis antipyretica were determined. In Morava river experiment this aquatic moss was used to determine bioavailable fraction of cadmium and the moss bag technique were compared with another methods for phytotoxic metals determination.
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Rhodium in the environment
Ondreášová, Klára ; Nevrlá, Jana (referee) ; Komendová, Renata (advisor)
This bachelor thesis focuses on the characteristic of rhodium, its use in the automotive industry, the occurrence in environmental compartments (air, soil, vegetation, water), accumulation and transformations. In this thesis there are also described methods of sampling for determination, the types of sample preparation, separation and preconcentration techniques necessary prior to instrumental analysis. The work also focuses on the most commonly used analytical methods of rhodium determination, which are spectrophotometric methods, AAS, ICP-AES and ICP-MS.
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Palladium in the environment
Hajdová, Jana ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This work is focused on palladium in the environment. Its use is especially in the automobile industry as catalytic converters of motor vehicles, but also is applied in dental, jewelry making and electrical appliances. The release of this metal from automobile catalysts is getting into all environmental compartments (soil, road dust, water, plants), where goes to its accumulation. It can be a part of the food chain and cause health risks to humans. The work also focuses on methods of sampling, preconcentration and methods, which can determined palladium in environmental samples (spectrophotometric methods, AAS, ICP-AES and ICP-MS).
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