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Interakce mezi Ti-Al-Nb taveninou a Y2O3 kelímky
Barták, Tomáš ; Dlouhý, Antonín ; Dočekalová, Kateřina ; Zemčík, L.
The present paper focuses on interactions between intermetallic melts (Ti-46Al-7Nb-0.7Cr-0.1Si-0.2Ni alloy (at%)) and ceramic crucibles based on the Y2O3 refractory. Different levels of superheat and exposure time are taken into account. Vacuum induction melting (VIM) experiments were performed using the vacuum furnace BALZERS VSG 02. The controlled argon atmosphere inside the furnace volume was kept at the pressure level of 0.133 bar during the melting experiments. The reactions at the melt - crucible interface were studied by means of scanning electron microscopy (SEM) equipped with the energy dispersive x-ray analyzer (EDX). There has been clear benefit when a common refractory like alumina has been replaced by yttria. However, the results obtained in this study show, that the long - term exposure at melting temperatures above 1650°C lead to notable reactions at the interface. We discuss the stability of the melt - ceramic system using principles of thermodynamic equilibrium.

Radioactive waste management in the department of nuclear medicine
VENCLÍK, Zdeněk
Radioactive waste management in the department of nuclear medicine is a complex process in which it is necessary to obey a number of lawful orders. These are based on physical and chemical properties of the radionuclide sources. At present these regulations particularly include Act No. 18/1997 Coll., on Peaceful utilisation of nuclear energy and ionizing radiation (the Atomic Act) and amendment to and alteration of some related acts in the wording and implementing Decree No. 307/2002 Coll., on Radiation Protection (which repeals Decree No. 184/1997 Coll.) in the wording of Decree No. 499/2005 Coll., which amends the Decree of the Czech National Council for nuclear safety No. 307/2002 Coll., on Radiation Protection. This legislation regulates the management of radioactive waste as a whole and deals with specific radionuclides in the annexes. It is necessary to comply with legislation whether the radioactive waste is generated in the actual production of radionuclides or during their diagnostic and therapeutic applications. All production and application processes give rise to certain materials contaminated with radionuclide sources but without the possibility of their further use. These contaminated and unusable materials are called radioactive waste. Radioactive waste arising from operation of nuclear medicine is basically divided into solid, liquid and gaseous. Solid radioactive waste is collected in refrigerators and lead safe deposits, depending on whether the waste is infectious or not. Liquid waste goes through the process of dilution in most cases, when there is a decrease of the volume activity limits and subsequent discharge to sewer. Gaseous waste is a negligible component of radioactive waste produced at nuclear medicine departments, so it is not often dealt with in more detail. No matter what kind of waste, the process of its disposal has a common goal of reducing its activity below specified limits (clearance levels), so that the waste can be without greater risk moved or released and disposed of as other, non-radioactive waste.


Open-air exhibition of rock types in Všeradice - proposal of the scientific scope
Žák, Karel ; Bosák, Pavel ; Cílek, Václav ; Mikuláš, Radek
The report contains scientific evaluation of the plan of the Všeradice Municipal Office for construction of open-air exhibition of rock types of the Barrandian area. General scope of the planned exhibition, as well as suitable rock types are proposed.


The Former Church of St. Lawrence under Petřín at Malá Strana in Prague
Bělohlávková, Monika ; Royt, Jan (advisor) ; Pučalík, Marek (referee)
Resumé This bachelor's work concernes with history of The former church of St. Lawrence under Petřín on Malá Strana in Prague, today which services as concert and exhibition hall of festival The Prague's spring and The Club of friends of festival The Prague spring's. This work endeavoures to take down build and history developement od the church, rich mural and general exoneration of this object, which was provided during 90th years of 20 th century. This exoneration was related to mainly return originaly wiew of sacral space to this object. Originaly form of the church was sacral, but during 19 th century this former church was rebuild on dwelling house.The exoternation concerned about large restauration of wall paintings, which was discovered during restoratione's works. The oldest discovered paintings stems from Romanesque period, but we can see here mural from Gothic, Renaissance and Baroque periods. Keywords: Gothic architecture Prague Plantation Nebovidy Former the church of St. Lawrence under Petřín / on Újezd / in Nebovidy Restauration of wall paintings Pages 42 Words 14 159 Marks (without interspace) 78 316 Marks (cum interspace) 92 837 Paragraphes 295 Lines 1423

Vliv vybraných kardiovaskulárních léčiv nalézaných ve vodním prostředí na ryby
STEINBACH, Christoph Antonius
Cardiovascular pharmaceuticals are among the most prescribed drugs. As a result of the high consumption, these pharmaceuticals have been frequently detected in waste and surface waters. Verapamil, diltiazem and atenolol are very important representatives of cardiovascular pharmaceuticals; therefore, the present research focused on their acute and sub-chronic effects, bioconcentration, half-life time and metabolism in fish. Moreover, unified protocol for the quantitative assessment of histopathological alterations on the heart ventricle and coronary blood vessels employing heart index calculation was developed with the aim to better assess histopathological changes in fish heart which is one of the targets of cardiovascular pharmaceuticals and other chemicals. The effects caused by high concentrations of the studied substances, verapamil, diltiazem and atenolol, in fish can be considered similar to the therapeutic effects and side effects that are found in humans. The acute exposure to verapamil at the human therapeutic plasma level reduced the heart rate in common carp embryos and larvae. In addition, the acute and chronic exposure to this substance caused peripheral edema and gastrointestinal haemorrhage in carp. Similarly, the histological changes in heart and the blood vessels of the liver in diltiazem exposed rainbow trout suggested vasodilatation similar to the pharmacological effect of diltiazem in the human body. In rainbow trout sub-chronically exposed to atenolol at a human therapeutic blood plasma concentration, histopathological changes in the cardiovascular system were found. The bioconcentration of verapamil, diltiazem and atenolol in fish can be classified as low. Bioconcentration factor (BCF) of verapamil in whole body homogenates of common carp ranged between 6.6 and 16.6. The BCF of diltiazem was also relatively low (0.5-194) in analysed tissues of trout, following the order kidney liver muscle blood plasma. BCF of atenolol in rainbow trout tissues was the lowest among the tested substances (BCF = 0.002-0.27), following the order of liver > kidney > muscle. In the blood plasma, the concentration of atenolol was below the limit of quantification. Verapamil showed a longer half-life time (10.6 days) in fish compared to the human body, indicating the slow rate of biotransformation and/or elimination of verapamil in fish. Estimated half-life times of diltiazem in liver (1.5 h) and kidney (6.2 h) were in the same order of magnitudes as those determined for the human blood plasma. The half-life time of atenolol in trout was not studied, because of its very low bioconcentration. In diltiazem exposed rainbow trout, 8 groups of metabolites of diltiazem with 17 different isoforms were identified using liquid chromatography/high resolution mass spectrometry method. Diltiazem was found to undergo a biotransformation involving desmethylation, desacethylation and hydroxylation in fish. These results showed that diltiazem was metabolised in fish in a similar way like in the human body by desmethylation and desacethylation. On the other hand, hydroxylation, which was involved to a minor extent, seemed to be species specific. Verapamil had no effect on early life stages of common carp at the environmentally relevant concentration after one month lasting exposure. On the other hand, atenolol and diltiazem in environmentally realistic concentrations caused after 42-day exposure some physiological changes in rainbow trout. Namely, atenolol affected haematological and biochemical parameters of the blood in exposed rainbow trout and diltiazem caused changes in the activity of antioxidant enzymes in trout liver and gills. These data indicated that atenolol and diltiazem, when present in the aquatic environment, could be a source of sub-lethal detrimental effects in fish.

Revitalization Program of Floral Garden in Kromeriz
Sedlák, Miroslav Gabriel ; Foretník, Jan (referee) ; Nový, Vítězslav (advisor)
The development of the town represented a key turning point in the life of the Flower Garden. Its entrance was relocated from the arcade in the upper part of the garden to its side, via the cour d'honneur. It means that visitors leave not having experienced the genius loci of the Flower Garden, since they entered the middle part of the garden “exhibition” without any previous explanation. The main idea of the entire project is to restore the garden into its original condition, which shall include the opening of a central pavilion and the possibility to enter the garden upon the “introduction” on the arcade in the upper part of the central axis. The project attempts to make use of the existing cour d'honneur as much as possible, which is finely renovated in order to be able to comply with the current requirements for a UNESCO World Heritage Site entrance building. The existing entrance building and cour d'honneur feature a foyer, restaurant, restaurant facilities and exhibition areas and supply off-loading area. The projected area features a new curve-defined exhibition area which represents reminiscence of a unique arcade. The new element is located in the upper third of the projected area and it is embedded in the surrounding terrain to create shallow passageway between the gardens. This embedding creates angularities running in opposite directions, one of which is designed as a ramp connecting the terrace on the arcade and the projected area. A florist’s is reconstructed in the lower part of the gardens (it is expected to be partly independent) with no relation to the applicable plan area. The florist’s is also interlaced with the axes of the Flower Garden, with the vision of the renovation of "rabbit’s hillock" and the reconstruction of a bird house with a body of water.

Research Report on Condition Assessment of Wood-destroying Damage to Log Walls of a Landless Person's Cottage of Leskovec (orig. No. 70) and a Cottage of Lužná (orig. No. 28) now in the Museum in Rožnov pod Radhoštěm
Kloiber, Michal ; Hrivnák, Jaroslav ; Bláha, Jiří
The subject of the research report was to assess the condition of and identify the wood-destroying damage to the walls of a landless person's cottage of Leskovec and a cottage of Lužná, two log structures that are part of the exhibition at the Wallachian Museum in Rožnov pod Radhoštěm. The report focused on locating points, classifying the degree of damage, determining the extent of concealed attack by the means of non-destructive devices, specifying whether wood is subject to a fungal attack (mycological damage) or insect attack (entomological damage) and drawing the results obtained in the plan documentation. The report was based on direct and mediated visual observation using an endoscope and mainly on measurements taken using a resistance microdrilling device and also on ascertainment of mechanical properties of wood using expanding jaws in the borehole. Based on the results, specific procedures for rehabilitation measures were designed and elements designed for structural rehabilitation were marked in the drawing documentation.