The aim of the thesis is to determine the levels of the physical and mechanical properties of chosen sedimentary (siliciclastic) rocks and also to describe their microstructural nature. With respect to the intended use of the studied material (building stone raw material) the laboratory testing methods are presented. The samples were taken from the drill cores and also from the surface blocks in locality "Zlatý lom" Březín situated in western Bohemia. The microstructural phenomena in the samples were studied using optical microscopy and digital image analyses. According to Folk's classification (1980) the name of the rock was lithic arkose. The strength testing methods were represented by unconfined compressive strength and the Brazilian test. The rest of the mechanical parameters were determined in form of Young's modulus, shear modulus and Poisson's ratio. Special emphasis was given to the hydric expansion (after full immersion) test. The other physical methods were used in order to describe the pore space and real density of samples. For this purposes the absorption test, mercury intrusion porosimetry and helium pycnometry were performed. Besides the porosity value, the pore-size distribution histograms were obtained. In order to calculate the theoretical density of the rock MINLITH and MODES...

The thesis deals with motor oil with the same viscosity class 5W-30. Five samples were monitored for new oil and two samples of the used motor oil of the same specification. Their physical and mechanical properties were compared depending on temperature. The first part is focused on the production of motor oils and their classification. In subsequent chapters their functions and features are described. The last part includes the description of methodology, the actual measurement, graphical and statistical processing of data, comparing results and conclusions.

The thesis deals with HDPE modification by crosslinking. In the theoretical part, data available in the literature were reviewed. Modifications of the selected HDPE copolymer grade were carried out in a kneading device Brabender using 25 ml chamber size. After having optimized process conditions, there were performed a series of experiments in dependence on concentration of the initiator. Reological properties of polymer samples were investigated by melt flow indexes measured under different conditions. Changes in crystallinity and melting temperatures were evaluated from DSC heat flow measurements. The samples meeting characteristics supposed were selected for measuring complex viscosity on the Rheometer AR-G2 TA and for testing some mechanical properties on the device Zwick.

At first this diploma thesis tests and compared selected physical and mechanical properties of various construction materials. Furthermore, thesis compares results with measured values determined by manufacturer. In next part of thesis is de-signed similar wall composition which is differs only by sheeting material. On every wall composition was calculated heat transmittance. Compositions are compared with each other, further there are compared economically.

This diploma thesis is interested in effective defense against necrosis of ashes. This disease influ-ences the ash population throughout whole Europe at present. Part of the diploma thesis is inte-rested in function of the ash patosystem. Within this research was realised complex analysis of the soil focused on physically-chemical and chemical atributes of the soil. On the partial variants were aplicated preparations with fungicidal behavior which were applied on the surface of the assimilation part of the plant. Substances should worked negative against successful germination of the ascospores on the leaves of the affected trees. In the second direction of the research was used nitrogen fertilizers which should positively influenced vitality of the host trees and together accelerated decomposition infected saps on the soil surface. Efficiency of defensive measures was evaluated with help of the periodical evaluation of health condition of the treated trees on the research areas. To this rating was used methodology Health condition the forest of ashes evaluation (Rozsypálek, 2015). Efficiency of the substance takes effect by braking or complete stopping worsening health condition. For stopping worsening health condition was recommended applying 20-25 l. ha concentrate Vermaktiv Stimul S16 with ionic sulfur in a higher proportion. Ratio of dilution with water is 1:50 – Vermaktiv S16 – water. As another active substance in relation with health vitality was evaluated ammonium sulfate. This application is implemented on the soil surface with recommended ration 750 kg. ha which represents 150 kg pure nitrogen per 1 ha.

This diploma thesis primarily focuses on thermal modification of wood with superheated steam and its effect on elasticity and strength. The sample tested was 200 pcs of bending samples and 200 pcs compressive samples of European beech. These samples were divided into ten groups. One group was referential and the remaining nine groups were modified using different temperatures and during different time intervals. The main goal was to determine density, modulus of elasticity and rupture and to discover their dependence on the chosen mode of modification. The next part contains the analysis of the effect of thermal modification with superheated steam on the acoustic properties and the colour of wood. In the last part, the mass loss and the change in equilibrium moisture content was analysed in relation to the modification mode.

This Masetr thesis looks into weathering pits of nature park Česká Kanada. The theoretical part of the thesis investigates research of weathering pits done in the Czech Republic as well as abroad. The practical part deals with weathering pit-bearing as well as weathering pitabsent blocks of rock within the study area. It describes their geological-geomorphological environment and attempts to find differences between the weathering pit-bearing and absent blocks (the presence of cracks, altitude, landforms, shape of the rock block and more). Furthermore it was established that a suitable rock block morphology (respectively the existence of horizontal plane) is important for formation of weathering pits. It also studies water properties in selected weathering pits, relationship of overhangs to prevailing wind directions. A correlation between overhang and wind direction was found in sense that NW to W winds correspond with overhang formation on eastern sides of weathering pits. Water in weathering pit of Čertův kámen located in sunny bare landscape shows significantly different properties in comparison with water properties of remaining weathering pits located in forrested areas.

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