|
|
Development of thermal a acoustic insulations based on secondary raw sources from textil industry
Kosturová, Andrea ; Třísko, Pavel (referee) ; Zach, Jiří (advisor)
The objective of the presented diploma thesis is to evaluate the influence of modification on surface layer of products with their base structure from organical fibers and on the ability to resist increased humidity. Emphasis is puted on the description of humidity propagation in fiber materials ant he approximation of secondary waste from the textile industry as a potencional material for thermal insulation. The end of the theoretical part focuses on the types of possible surface treatment to prevent the ingress water into the structure of the material. The practical part verifies the selected type of modification of the surface layer of three materials choosen as test ensemble. After applying surface treatment, the effect of treatment on humidity sensitivity and water absorption was assessed. The determination of the thermal conductivity coefficient, the short-term absorption at partial immersion and the determination of the sorption humidity were made.
|
|
|
Effect of moisture on the electrical properties of silicate composites
Karlíková, Helena ; Kusák, Ivo (referee) ; Rovnaník, Pavel (advisor)
This work deals with study on the dependence of electrical properties on the moisture content in silicate composites. The theoretical part contains information about the electrical properties of cement-based and alkali-activated binders, as well as knowledge on moisture parameters and the presence of moisture in the material structure. Samples of cement-based mortars and alkali-activated slag with a graphite powder in the range of 0–18 per cent by weight were produced and quartz sand was used as filler in the experimental part. The samples were provided with copper electrodes and saturated with water after hardening. The electrical properties of the mortars were monitored by means of impedance spectroscopy during the gradual drying of the samples. The effect of microstructure has been studied using scanning electron microscopy and mercury intrusion porosimetry. The results indicate that a significant increase in electrical resistance occurs only when the relative sorption humidity content is below 20 per cent in the 40–5000 Hz frequency range.
|
|
|
Effect of moisture on the electrical properties of silicate composites
Karlíková, Helena ; Kusák, Ivo (referee) ; Rovnaník, Pavel (advisor)
This work deals with study on the dependence of electrical properties on the moisture content in silicate composites. The theoretical part contains information about the electrical properties of cement-based and alkali-activated binders, as well as knowledge on moisture parameters and the presence of moisture in the material structure. Samples of cement-based mortars and alkali-activated slag with a graphite powder in the range of 0–18 per cent by weight were produced and quartz sand was used as filler in the experimental part. The samples were provided with copper electrodes and saturated with water after hardening. The electrical properties of the mortars were monitored by means of impedance spectroscopy during the gradual drying of the samples. The effect of microstructure has been studied using scanning electron microscopy and mercury intrusion porosimetry. The results indicate that a significant increase in electrical resistance occurs only when the relative sorption humidity content is below 20 per cent in the 40–5000 Hz frequency range.
|
|
|
Development of thermal a acoustic insulations based on secondary raw sources from textil industry
Kosturová, Andrea ; Třísko, Pavel (referee) ; Zach, Jiří (advisor)
The objective of the presented diploma thesis is to evaluate the influence of modification on surface layer of products with their base structure from organical fibers and on the ability to resist increased humidity. Emphasis is puted on the description of humidity propagation in fiber materials ant he approximation of secondary waste from the textile industry as a potencional material for thermal insulation. The end of the theoretical part focuses on the types of possible surface treatment to prevent the ingress water into the structure of the material. The practical part verifies the selected type of modification of the surface layer of three materials choosen as test ensemble. After applying surface treatment, the effect of treatment on humidity sensitivity and water absorption was assessed. The determination of the thermal conductivity coefficient, the short-term absorption at partial immersion and the determination of the sorption humidity were made.
|
guest ::
