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The theoretical part of the diploma thesis with the topic "Effect of bio-component on the automotive gasoline properties" contains a summary of basic fuels for spark ignition engines, their basic properties, and the legislative requirements. This part also deals with the theory of measurement of density, viscosity and shear stress. In the experimental part of thesis are described the measurement of the physical and mechanical properties of petrol, buthanol and their blend sand determination of their temperature dependences. The results are presented in the tables and are shown in the charts. Obtained results are discussed with the thematic scientific contributions.

This thesis deals with dependency of density and dynamic viscosity on temperure of motorcycle engine oils. The literary part contains basic knowledge about lubricant as such, basic informations about oils, describes principles of chosen tests of motorcycle engine oil and its basic function and physical properties. In the practical part is described procedure of collecting the samples of motorcycle engine oils and its description, metodology of measurement, graphical processing and statistical processing of the collected data.

This work deals with the evaluation of the influence of weed intensity on stand density. Weed infestation was observed in Triticum aestivum and Brassica oleacea. The difference between autumn and spring composition of plant species was observed. Thlaspi arvense, Capsela bursa pastoris, and Galium aparine were the most common in the autumn measurement of Triticum aestivum. In spring Lamium purpureum predominated. In the autumn period, Brassica oleacea species were mostly Thlaspi arvense, Capsela bursa pastoris and Tripleospermum inodorum. In the spring, Capsela bursa pastoris, Veronica hederifolia and Viola arvensis. According to the statistical evaluation, the results are highly statistically significant; in the less dense stands of the wheat species Convolvulus Arvensis, Avena Fatua, Aegopodium Podagaria were found. In the less dense rape, Viola Arvensis and Capsela Bursa Pastoris were found.

This thesis describes the influence of selected additive on lubricating abilities of motor oil. The first part describes the basic properties of engine oils, types of additives, their production and distribution. Further, basic tribological properties such as friction, wear, lubricity, lubricity and viscosity are described. In the second part of the thesis was measured the influence of additive on lubricating ability of engine oil. The measurement was divided into two basic parts. The first part was devoted to the measurement of abrasion and the second was to measure the density and viscosity of the separate engine oils and the additive additive. The measurement results were tabulated. At the end, a summary and discussion of the measured results was performed.

This thesis deals with the degradation of hydraulic oil used in the hydraulic circuit of tractor. In the first part of thesis is created a literary overview about hydraulic oils, their distribution, properties and production. The experimental part deals with degradation of hydraulic oil. There is described a process of taking samples which are then measured to demonstrate the important features of the gradual degradation of the oil. These properties are density, viscosity and amount of chemical elements contained in the oil samples. In the last part of thesis the measured results are processed in tables and graphs. The results are further evaluated and accompained by the discussion.

In the potato production type, 380 {--} 400 m above sea level, was studied density 40 000, 45 000, 50 000, 55 000 plants per 1 ha on the yield potato, average number of tubers on the plant, proportion and average weight of tubers. The maximum yield of tubers were recorded at density 45 000 plants per 1 ha (varieties Impala, Adéla, Futura). Density grow it was not influence at proportion market tubers. Highest density growth the meaning reduction average weight of tubers.