Laboratorio di diffrazione RX su polveri XRPD
Italiano
Diffrattometro automatico per polveri Bruker AXS D8 Advance, operante in geometria θ/θ in trasmissione su capillari, dotato di camera riscaldante fino a T 1000°C e rivelatore PSD VÅntec-1.
high-temperature X-ray powder diffraction
The thermal behaviour of sacrofanite
The thermal behaviour of sacrofanite, the ABCABACACABACBACBACABABACABC 28-layer member of the cancrinite sodalite supergroup has been investigated in situ using laboratory focussing-beam X-ray powder diffraction data. Thermal expansion has been analysed from 303 to 873 K. A moderate anisotropy has been observed at T > 473 K, the c-parameter being softer than the a-parameter. At ca. 800 K the unit cell starts to compress owing to (partial) dehydration.
Thermal stabiliy of woolly erionite-K and considerations about the heat-induced behaviour of the erionite group
The thermal behavior of a woolly erionite-K sample (Lander County, NV, USA), chemical formula (Ca2.03 Na0.73 K2.52 Mg0.26)[Al8.22 Si27.78 O71.80 ]·35.94H2 O, was investigated in the 303–1173 K thermal range by in situ X-ray powder diffraction. Present data suggest a general thermally-induced volume contraction whose magnitude increases as(formula presented) ratio becomes smaller. An inverse correlation between(formula presented) ratio and Tdehydr is observed because higher(formula presented) ratio values are associated to lower dehydration temperatures.