Search results for "Elastic light scattering"
showing 3 items of 3 documents
GdBO3 and YBO3 crystals under compression
2021
High-pressure X-ray diffraction studies on nanocrystals of the GdBO3 and YBO3 rare-earth orthoborates are herein reported up to 17.4(2) and 13.4(2) GPa respectively. The subsequent determination of the room-temperature pressure-volume equations of state is presented and discussed in the context of contemporary publications which contradict the findings of this work. In particular, the isothermal bulk moduli of GdBO3 and YBO3 are found to be 170(13) and 163(13) GPa respectively, almost 50% smaller than recent findings. Our experimental results provide an accurate revision of the high-pressure compressibility behaviour of GdBO3 and YBO3 which is consistent with the known systematics in isomor…
Experimental and theoretical study of dense YBO3 and the influence of non-hydrostaticity.
2021
[EN] YBO3 is used in photonics applications as a host for red phosphors due to its desirable chemical stability, high quantum efficiency and luminescence intensity. Despite its fundamental thermodynamic nature, the isothermal bulk modulus of YBO3 has remained a contentious issue due to a lack of comprehensive experimental and theoretical data and its vibrational modes are far from being understood. Here, we present an experimental-theoretical structural and vibrational study of YBO3. From structural data obtained from synchrotron X-ray diffraction data and ab initio calculations, we have determined the YBO3 bulk modulus, isothermal compressibility tensor and pressure-volume (P-V) equation o…
Elastische Lichtstreuung an Polymeren
2008
Die elastische Lichtstreuung wird in vielen Gebieten der Polymerwissenschaft angewendet, um Strukturen in der Grosenordnung 102 – 105 A zu Charakterisieren. Mit dieser Methode konnen sowohl Dichte- als auch Anisotropiefluktuationen erfast werden, so das eine sehr detaillierte Beschreibung polymerer Strukturen moglich ist. Nach einer Einfuhrung in die theoretischen Grundlagen der elastischen Lichtstreuung wird ein kurzer Uberblick uber die experimentellen Methoden gegeben. Im Anschlus daran werden einige neuere Lichtstreuuntersuchungen als Anwendungsbeispiele erortert, wobei Fragen nach der Struktur amorpher Polymerer, der Netzwerkstruktur von Polymeren, der Phasentrennung bei Mehrkomponente…