Regensburg, Universiẗat, Diss., 2005.

Thesis--Göttingen. / In Periodical Room.

This master thesis deals with the surface treatment of parts made of plastic produced using FDM technology and design of technological device for surface treatment. The thesis describes FDM principles, according to performed experiments in a technological device there are suggested technological conditions for the surface treatment of parts made of ABS plastic. In the end of the thesis, there are calculated costs of the technological device and its operating costs, also mechanical properties, surface roughness and other specifications from before and after the treatment are compared.

The aim of this diploma thesis was to evaluate the occurrence of ketones and free fatty acids in milk of high-yielding cows. Ketosis is a very common metabolic disorder in dairy cows resulting in reduced milk production, fertility disturbance and more frequent occurrences of other diseases. Ketosis is not only a serious health problem, but also an economic problem, that can be avoided by balancing the feeding dose respecting the physiological needs of energy delivery after birth and at the beginning of lactation of high-yielding cows. The monitoring was carried out in 2016 at Chyšná, which is one of the centers of Agribusiness Košetice a.s. Owerall were 1407 cows monitored during the 6 utility tests (from January to June 2016). The occurrence of subclinical ketoses was defined by the content of ketones in milk (acetone and beta-hydroxybutyric acid). Critical was the period of the first 12 days of lactation, when the occurence of subclinical ketoses was the highest, the occurence of this disease was lower than in other breeds. At Chyšná breeding, the low incidence of subclinical ketoses is mainly influenced by zootechnical work and by working with the feed consultant and the company for the production of compound feeds. As a precautionary process, regular feed analysis and examination of free fatty acids and ketones in milk can be recommended.

This thesis deals with the stopping of hydration of alkali activated slag by organic solvents and investigates to what extent the selected organic solvent affects the results of the analyses. The solvents used were acetone, diethyl ether, ethanol, isopropanol and methanol, and this is because these are the most commonly used organic solvents in practice. Thermogravimetric analysis along with differential thermal analysis was used to assess the degree of influence of organic solvents on the alkali activated slag and Portland cement samples. Methanol and acetone affected the samples the most and the longer the sample was stored in the solvent, the more it reacted with the organic solvent. The adverse interaction of organic solvent was greatest for the Portland cement samples. Samples that were rinsed with diethyl ether prior to analysis had lower mass losses than samples that were not rinsed. In the case of alkali activated slag, it was found that the way in which the thermogravimetric results were affected by organic solvents was highly dependent on the activator used, with the smallest effect observed for Na2CO3 activation, while the largest effect was observed for NaOH activation at temperatures below 600 °C, and for higher temperatures for water glass activation.