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Preparation of pure metals - analysis of the materials purity using physical quantities.
Proschek, Petr ; Pospíšil, Jiří (advisor) ; Prokleška, Jan (referee)
The thesis deals with the purity of lanthanoids and their purification using the solid state electrotransport (SSE). This method is used for high-level purification of metals. This process is really slow and is suitable especially for need of science. For this method we have prepared the cer and praseodym samples in monoarc and applicated SSE process on them. Afterthat we measured RRR (residual resistivity ratio) using four-point connection of the samples of cer and praseodym before and after the purification process and compared the values. The metals after SSE method always show a higher RRR value which means the lower level of impurities. Powered by TCPDF (www.tcpdf.org)
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Extension of instrumental capabilities in cryomagnetic laboratory
Proschek, Petr ; Prokleška, Jan (advisor) ; Javorský, Pavel (referee)
Measurement of elastic properties (thermal expansion and magnetostriction) under (multi)extreme conditions is a difficult task. In the vicinity of the room temperature or above it an abundance of methods is available, with decreasing temperature and adding magnetic field and/or hydrostatic pressure their number is limited. Dilatometric cells (either planparaller or tilted plate design) provide superior sensitivity in low temperatures and applied magnetic fields, however, cannot be used in hydrostatic cell. Common choice for the measurement of thermal expansion under hydrostatic pressure are methods based on strain-gauges, with mediocre sensitivity and more importantly a difficult or even impossible usage at very low temperatures (T ≲ 3 K). Measurement of magnetic properties (especially magnetization) under (multi)extreme conditions is also a difficult task. In the vicinity of temperature 2 K and above it an abundance of methods is available, with decreasing temperature and adding magnetic field and/or hydrostatic pressure their number is limited. VSM system provides great sensitivity, but can not be used under 2 K and hydrostatic pressure. MPMS aparature provides pressure up to 9 GPa (diamond pressure cell), but still we can not apply lower temperatures than 2 K. Our aim is to develop a simple yet sensitive...
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Extension of instrumental capabilities in cryomagnetic laboratory
Proschek, Petr ; Prokleška, Jan (advisor) ; Javorský, Pavel (referee)
Measurement of elastic properties (thermal expansion and magnetostriction) under (multi)extreme conditions is a difficult task. In the vicinity of the room temperature or above it an abundance of methods is available, with decreasing temperature and adding magnetic field and/or hydrostatic pressure their number is limited. Dilatometric cells (either planparaller or tilted plate design) provide superior sensitivity in low temperatures and applied magnetic fields, however, cannot be used in hydrostatic cell. Common choice for the measurement of thermal expansion under hydrostatic pressure are methods based on strain-gauges, with mediocre sensitivity and more importantly a difficult or even impossible usage at very low temperatures (T ≲ 3 K). Measurement of magnetic properties (especially magnetization) under (multi)extreme conditions is also a difficult task. In the vicinity of temperature 2 K and above it an abundance of methods is available, with decreasing temperature and adding magnetic field and/or hydrostatic pressure their number is limited. VSM system provides great sensitivity, but can not be used under 2 K and hydrostatic pressure. MPMS aparature provides pressure up to 9 GPa (diamond pressure cell), but still we can not apply lower temperatures than 2 K. Our aim is to develop a simple yet sensitive...
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Preparation of pure metals - analysis of the materials purity using physical quantities.
Proschek, Petr ; Pospíšil, Jiří (advisor) ; Prokleška, Jan (referee)
The thesis deals with the purity of lanthanoids and their purification using the solid state electrotransport (SSE). This method is used for high-level purification of metals. This process is really slow and is suitable especially for need of science. For this method we have prepared the cer and praseodym samples in monoarc and applicated SSE process on them. Afterthat we measured RRR (residual resistivity ratio) using four-point connection of the samples of cer and praseodym before and after the purification process and compared the values. The metals after SSE method always show a higher RRR value which means the lower level of impurities. Powered by TCPDF (www.tcpdf.org)
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