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The preparation and characterisation of electrical properties of graphene CVD monocrystals
Hulva, Jan ; Rezek, Bohuslav (oponent) ; Mach, Jindřich (vedoucí práce)
Chemical Vapor Deposition (CVD) of graphene is the method of graphene synthesis capable of producing predominantly single layer graphene of large area. Part of the experimental work of this thesis is focused on the deposition and analysis of single-crystalline graphene domains grown by CVD on a copper foil. These domains are analyzed by the optical microscopy, scanning electron microscopy, atomic force microscopy and Raman spectroscopy. The next part of the work was devoted to iden- tification of defects present on the Cu foil after the deposition of graphene by means of energy dispersive X-ray spectroscopy. The amount of the defects was reduced by the adjustment of the deposition system although not all types of the defects were completely removed. Electronic transport properties of deposited graphene layers were performed in the last part. The results contain measurement of graphene in vacuum with applied back gate voltage and low temperature measurement with applied magnetic field.
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Experimental study on satellite´s passive thermal-regulation units
Mateášik, Timko Marek ; Mašek, Jakub (oponent) ; Lazar, Václav (vedoucí práce)
Master‘s thesis examines the eect of thermal interface materials on thermal contact conductance and resistance. The thesis focuses on application of the thermal interface materials for the thermal contact conductance enhancement in the miniaturised heat switch and the spacecraft generally. Theoretical part of this work briey reviews variety of passive thermal control systems used in spacecraft, including thermal interface materials and explains the background of this work. This work further a reviews of the variety of thermal interface materials, especially coatings and foils, and introduce the selection of suitable thermal interface materials. Experimental part of this work examines surface parameters, thermal conductivity and microhardness of copper specimens which serve as substrate for pure silver coating. Further examines the measurement conditions, evaluation methods and experimental measurements. The experimental measurements are carried out in thermo-vacuum test chamber and conclusion are made based on the results. The recommendations for further work are made.
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Experimental study on satellite´s passive thermal-regulation units
Mateášik, Timko Marek ; Mašek, Jakub (oponent) ; Lazar, Václav (vedoucí práce)
Master‘s thesis examines the eect of thermal interface materials on thermal contact conductance and resistance. The thesis focuses on application of the thermal interface materials for the thermal contact conductance enhancement in the miniaturised heat switch and the spacecraft generally. Theoretical part of this work briey reviews variety of passive thermal control systems used in spacecraft, including thermal interface materials and explains the background of this work. This work further a reviews of the variety of thermal interface materials, especially coatings and foils, and introduce the selection of suitable thermal interface materials. Experimental part of this work examines surface parameters, thermal conductivity and microhardness of copper specimens which serve as substrate for pure silver coating. Further examines the measurement conditions, evaluation methods and experimental measurements. The experimental measurements are carried out in thermo-vacuum test chamber and conclusion are made based on the results. The recommendations for further work are made.
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The preparation and characterisation of electrical properties of graphene CVD monocrystals
Hulva, Jan ; Rezek, Bohuslav (oponent) ; Mach, Jindřich (vedoucí práce)
Chemical Vapor Deposition (CVD) of graphene is the method of graphene synthesis capable of producing predominantly single layer graphene of large area. Part of the experimental work of this thesis is focused on the deposition and analysis of single-crystalline graphene domains grown by CVD on a copper foil. These domains are analyzed by the optical microscopy, scanning electron microscopy, atomic force microscopy and Raman spectroscopy. The next part of the work was devoted to iden- tification of defects present on the Cu foil after the deposition of graphene by means of energy dispersive X-ray spectroscopy. The amount of the defects was reduced by the adjustment of the deposition system although not all types of the defects were completely removed. Electronic transport properties of deposited graphene layers were performed in the last part. The results contain measurement of graphene in vacuum with applied back gate voltage and low temperature measurement with applied magnetic field.
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