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Utilization possibilities of industry gypsum and secondary materials containing for preparation of composites
Weiglová, Jana ; Šoukal, František (referee) ; Opravil, Tomáš (advisor)
The work studies the possibilities of the utilization of secondary raw materials produced by power industry. It addresses mainly the gypsum by-products and fluidized coal combustion ash. As for the secondary raw materials the content of sulphites is observed and the dependences of their transformation to sulphides via natural oxidation by air oxygen or by addition of adequate oxidant are studied. The work follows with describing the effect of sulphides contained in raw materials on the mechanical properties of composites prepared from several various matrices such as alumina or portland cement, lime or portland clinker. As for pure portland clinker the ability to retard the setting is also observed. The amount of contained sulphites is measured volumetrically via indirect titration of iodine surplus by sodium thiosulphate with the starch size as the indicator.
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Development of a New Repair Mortar Using Secondary Raw Materials
Figala, Petr
This paper deals with the research of a new repair mortar modified with secondary raw materials. The aim of the work is to develop a material characterized by chemical resistance suitable for the rehabilitation of sewer concrete structures. Resistance to aggressive sulphate solution and to attack by sulfuric acid was chosen as the key parameters for the choose of a final mixture. Chemical resistance was tested by simulating the exposure environment in laboratory conditions, according to the methodology of DIN 19573. The obtained results show that by suitable modification of the reference mortar it is possible to maintain the values of physical-mechanical characteristics and improve the chemical resistance of test samples. The final mixture will be further tested in field conditions.
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Development of electrophoretic method for determination of sulphate in blood plasma
Hnízdilová, Lucie ; Křížek, Tomáš (advisor) ; Hraníček, Jakub (referee)
Cílem této bakalářské práce bylo vyvinout metodu pro stanovení síranů v krevní plazmě pomocí kapilární zónové elektroforézy. Byla použita křemenná kapilára o vnitřním průměru 50 μm a efektivní délce 41,5 cm. Plazmatické proteiny byly sráženy acetonitrilem. Jako optimální základní elektrolyt byla určena 0,4M kyselina mravenčí s 15mM chromanem draselným. Separační napětí bylo 25 kV. Vzorek byl dávkován napětím -5 kV po dobu 40 s. K vyhodnocení byla využita nepřímá UV detekce při 260 nm. Vzhledem ke složité matrici je vhodné provést kvantifikaci metodou standardního přídavku. Po vztažení ploch píků na vnitřní standard (500μM chlorečnany) byla relativní směrodatná odchylka 5,97 %. Výhodou této metody oproti dříve používaným srážecím metodám je krátká doba analýzy a jednodušší úprava vzorku. Klíčová slova kapilární elektroforéza, anorganické ionty, sírany, krevní plazma
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Utilization possibilities of industry gypsum and secondary materials containing for preparation of composites
Weiglová, Jana ; Šoukal, František (referee) ; Opravil, Tomáš (advisor)
The work studies the possibilities of the utilization of secondary raw materials produced by power industry. It addresses mainly the gypsum by-products and fluidized coal combustion ash. As for the secondary raw materials the content of sulphites is observed and the dependences of their transformation to sulphides via natural oxidation by air oxygen or by addition of adequate oxidant are studied. The work follows with describing the effect of sulphides contained in raw materials on the mechanical properties of composites prepared from several various matrices such as alumina or portland cement, lime or portland clinker. As for pure portland clinker the ability to retard the setting is also observed. The amount of contained sulphites is measured volumetrically via indirect titration of iodine surplus by sodium thiosulphate with the starch size as the indicator.
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The chemical and physical parameters of precipitation waters in the Stropnicko region.
MORBICEROVÁ, Iveta
This work aimed to evaluate long-term changes of selected chemical and physical parameters of rainwater from their own rain gauge stations Stropnicko. Chemical and physical parameters influence the rate of loss of substance in the landscape through the soil environment. In particular, the amount and concentration of dissolved sulphates and nitrates, affecting the value of the current pH. Samples were taken from their own rain gauge stations Stropnicko. Names of stations from which samples were taken are Horní Stropnice, Nakolice, Paseky and Nové Hrady. Rainfall were measured between the years 2005-2011 and were subjected to chemical analysis.
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