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Testing of polymeric materials under climatic conditions of Antarctica
Mičkal, Petr ; Sluková, Michaela (referee) ; Krmíček, Lukáš (advisor)
The bachelor's thesis generally deals with polymer materials and evaluates the possibility of testing their resistance to extreme climates of Antarctica. Described herein are various polymer materials, their characteristics, structure, properties and more thorough and detailed descriptions of selected polymers. The next section describes the basic types of degradation these polymers are exposed to, when facing the extreme conditions of the Antarctic climate. The practical part contains evaluations of tests made on the degraded polymer materials that were collected in Antarctica during the southern Antarctic season of 2013-2014 by Ing. Bc. Pavel Kapler, Ph.D, who is a superintendent at the Czech scientific station JG Mendel.
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Selected glasses of Ge-Se-Te system
Černošková, E. ; Hejdová, M. ; Černošek, Z. ; Holubová, J. ; Todorov, R. ; Vlček, Milan
Bulk glasses Ge30Se70-xTex for (x = 0, 10, 20) were prepared by direct synthesis. Thermal evaporation was used for preparation of thin films. The glass transition temperature of the bulk samples and decrease with increasing Te, but Tg of films with tellurium was not found. Crystallization temperature, Tc, for both bulk samples and films were close each to other. Comparing of Raman spectra - the corresponding Raman bands showed that medium-range order of bulks and thin films are partly different. 77Se MAS NMR of Ge30Se70 glass detected resonance of only Ge-Se-Ge (420 ppm, 98 %) and Se-Se-Se (837 ppm, 2 %), eliminating outrigger raft model and the structure of the studied glasses is probably close to Continuous Random Model.
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