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Monitoring of the tin release to the canned fruit from the used packaging
Flajs, Roman ; Vránová, Dana (referee) ; Diviš, Pavel (advisor)
This master’s thesis deals with the issue of the release of tin in canned fruit of used packaging. The theoretical part of the thesis is described canning fruit as raw material, its composition, methods of preservation, basic technological operations fruit processing, manufacture of compote, manufacture of metal packaging, marches corrosive metal packaging, chemical behavior of tin in foods and toxicity, methods for the determination of tin in foods with a focus on optical emission spectrometry with inductively coupled plasma. I the experimental part of the thesis was first ICP-OES optimized before to analysis of the 20 different samples compote purchased in chain stores. Tin concentration was determined by a fixed proportion compote. Measured concentration of tin were compared with the maximum permissible value in canned foods, which is allowed by European legislation. The tin content in all analyzed compote did not exceed the legislative limit of 200 mg/kg. The highest concentration of tin has been measured in sample conserved apricots namely 88,6 ± 2,8 mg/kg.
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The issue of determination of tin in environmental matrices
Bušinová, Markéta ; Sommer, Lumír (referee) ; Doležalová Weissmannová, Helena (advisor)
This diploma thesis deals with the retrieval of the content of tin in environmental media, the circulation in them and possibilities of the determination of tin in the environment. Summarizes available information on the properties of tin and its compounds, the occurrence and circulation of tin in environmental and determination of tin in environmental media, attention is paid to the determination of total tin content using method of ET-AAS. The experimental part is focused on optimization methods of determination for the ET AAS and selection of a suitable extraction procedure for determination of total tin content in soils and sediments. The best procedure for the determination of tin in the ET-AAS was applied to samples of soil, sediment and water. As the optimum matrix modifier was chosen the solution of Pd (NO3)2 in 5% ascorbic acid, the optimum pyrolysis temperature was 1400 °C and atomization temperature 2400 ° C. Neither of extraction procedures examined were found to be an appropriate procedure for the determination of tin in environmental samples and further work is necessary to optimize the method of separation.
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Determination of tin in canned fruits
Šťávová, Elena ; Hrstka, Miroslav (referee) ; Diviš, Pavel (advisor)
This bachelor’s thesis deals with determination of tin in canned fruits. Fruit processing, manufactory of compotes, manufactory of metal packaging products, corrosion of cans, chemical behaviour of tin in food, its potential toxicity, possibilities for the determination of tin in food and characterization of inductively coupled plasma optical emission spectrometry are described in theoretical part. In experimental part, ICP-OES technique was firstly optimized and then 28 different compotes purchased at common stores were analysed. The concentration of tin was determined only in fruit juice due to the easier sample preparation, even though quantity of tin in the solid part and in the juice can differ. However, the difference is not too big. Measured concentrations of tin were compared with the maximum permissible level of tin in canned food determined by European legislation. None of them exceed the 200 mg/kg level. When processing the results, it was found that the coating of the can has a significant influence on the content of tin in canned fruits. Concentrations of tin in laquered cans were significantly lower than in unlaquered cans.
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Tin and his species in the environment
Bušinová, Markéta ; Moos, Martin (referee) ; Doležalová Weissmannová, Helena (advisor)
Presented bachelor thesis is background research on tin and his species in the environment. Mainly deals with the effects of inorganic and organic compounds of tin on elements of environment. The work resumes accessible information about properties of tin and his compounds, entry of tin and his compounds into the elements of environment, cycle and occurrence of tin speciation in water, soils, sediments and biological materials.
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Confrontation of western and eastern spirituality: options and limitations of contemporary approaches the transcendent
KLOZAR, Karel
The thesis deals with examination of the transcendent in relation to the human being through intraspective and extraspective analysis of some typical differences of eastern and western approach to being. Pointing out some fundamental differences on extraspective level. Searching for possible similarities on intraspective level ? real, imaginary and possible. Inspiration with Jung's collective unconsciousness and individuation process as the possible key to understanding the essence of human as focus of relation of an universal and an individual. The transcendent as a collective goal, or source of conflict? Are eastern and western approaches the transcendent compatible? Is there some essence of the transcendent, which is universal and points to some unbiased form of experience? Integration of consciousness and unconsciousness as the fundamental joint of East and West.
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