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Liquid electrolytes for lithium-ion accumulators
Štichová, Zuzana ; Vondrák, Jiří (referee) ; Sedlaříková, Marie (advisor)
The aim of this master´s thesis was the measurement of electrical conductivity and dynamic viscosity of the electrolytes. Based on these measurements to verify Walden theorem between measured variables. Electrolytes were used on sulfolane base in combination with propylene carbonate and salt. The thesis also deals with the measuring method of dielectric properties of electrical and optical method with a refractometer. The freezing point of combination of sulfolan and propylene carbonate were determined by cryoscopy.
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Tomographic measurement of industrial parts at temperature below freezing point
Šárközi, Rudolf ; Oberta,, Peter (referee) ; Zikmund, Tomáš (advisor)
X-ray computed tomography presents and ultimate for non-destructive investigation of objects. Under normal circumstances is the object placed on stage and the temperature of the object is defined by ambient air. However there are also cases when observation at freezing or high temperatures is needed to reveal thermal stability of observed object. Naturally the size of used tomography equipment and the object just like form of cooling or heating are subjected to final design. This work provides a summary of used methods for temperature controlled tomography. Furthermore handles about design of cooling chamber capable to reach -40°C by preserving relative high X-ray transparency. As an addition that showed up as a response to additional requirements is here presented a heating chamber, in which the object can be maintained at 80°C . All test and scans were carried out on GE phoenix v|tome|x L240 industrial computed tomography scanner.
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Rheological properties analysis of heat transfer fluids
Neradil, Petr ; Hylský, Josef (referee) ; Frk, Martin (advisor)
This master thesis deals with the issue of heat transfer fluids for solar thermal system. It discusses the different types of solar systems and their use. It also describes the different types of heat-transfer fluids for solar thermal systems and analyzes the basic chemical composition of commercially available heat-transfer fluids. There are described the properties of these fluids and methods for measuring certain properties. The practical part deals with measuring the temperature dependence of density and dynamic viscosity of alternative and commercially available heat-transfer fluids, determining the freezing point and compares the results.
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The evaluation of milk quality in selected countries of European Union
POKORNÝ, Martin
The diploma thesis deals with the assessment of qualitative indicators of raw cow's milk supplies within the European Union (EU) and the Czech Republic (CR), de-pending on the year and course of the year. Within the EU average values for the observed period 2016-2020 were found for fat contents of 4.01 ? 0.26% and protein content of 3.39 ? 0.13%; in the CR 3.91 ? 0.11% and 3.46 ? 0.08%. The effect of the year within the EU countries was demonstrated only in terms of protein content (p <0.001). When evaluating the effect of individual months in EU countries, includ-ing the CR, statistically significant differences in fat (p <0.001) and protein (p <0.001) content were demonstrated. In summer, the values of both components in-creased, while in winter they decreased. The results of the evaluation of bulk milk samples purchased in the CR show, depending on the year, that the effect on the total bacteria count (p <0.001), residues of inhibitory substances (p <0.05) and freez-ing point of milk (p <0.001) was also found. The effect of the year was elicited for the total bacteria count (p <0.05) and the somatic cell count (p <0.001). From the point of view of milk sales, the quality of raw milk is a primary goal for the producer and at the same time a decisive factor in the monetization of this important animal commodity.
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Tomographic measurement of industrial parts at temperature below freezing point
Šárközi, Rudolf ; Oberta,, Peter (referee) ; Zikmund, Tomáš (advisor)
X-ray computed tomography presents and ultimate for non-destructive investigation of objects. Under normal circumstances is the object placed on stage and the temperature of the object is defined by ambient air. However there are also cases when observation at freezing or high temperatures is needed to reveal thermal stability of observed object. Naturally the size of used tomography equipment and the object just like form of cooling or heating are subjected to final design. This work provides a summary of used methods for temperature controlled tomography. Furthermore handles about design of cooling chamber capable to reach -40°C by preserving relative high X-ray transparency. As an addition that showed up as a response to additional requirements is here presented a heating chamber, in which the object can be maintained at 80°C . All test and scans were carried out on GE phoenix v|tome|x L240 industrial computed tomography scanner.
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|
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Rheological properties analysis of heat transfer fluids
Neradil, Petr ; Hylský, Josef (referee) ; Frk, Martin (advisor)
This master thesis deals with the issue of heat transfer fluids for solar thermal system. It discusses the different types of solar systems and their use. It also describes the different types of heat-transfer fluids for solar thermal systems and analyzes the basic chemical composition of commercially available heat-transfer fluids. There are described the properties of these fluids and methods for measuring certain properties. The practical part deals with measuring the temperature dependence of density and dynamic viscosity of alternative and commercially available heat-transfer fluids, determining the freezing point and compares the results.
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Liquid electrolytes for lithium-ion accumulators
Štichová, Zuzana ; Vondrák, Jiří (referee) ; Sedlaříková, Marie (advisor)
The aim of this master´s thesis was the measurement of electrical conductivity and dynamic viscosity of the electrolytes. Based on these measurements to verify Walden theorem between measured variables. Electrolytes were used on sulfolane base in combination with propylene carbonate and salt. The thesis also deals with the measuring method of dielectric properties of electrical and optical method with a refractometer. The freezing point of combination of sulfolan and propylene carbonate were determined by cryoscopy.
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