Phase behaviour, thermal expansion and compressibility of SnMo2O8

Compressibility and thermal expansion of cubic silicon nitride

Compressibility and thermal expansion of hydrous ringwoodite with 2.5(3) wt% H2O

Ringwoodite ( -Mg2SiO4) is the stable polymorph of olivine in the transition zone between 525–660 km depth, and can incorporate weight percent amounts of H2O as hydroxyl, with charge compensated mainly by Mg vacancies (Mg2+ = 2H+), but also possibly as (Si4+ = 4H+ and Mg2+ + 2H+ = Si4+). We synthesized pure Mg ringwoodite containing 2.5(3) wt% H2O, measured by secondary ion mass spectrometry (S...

Phase Transition and Thermal Expansion of MgSiO3 Perovskite.

Results from in situ x-ray diffraction experiments with a DIA-type cubic anvil apparatus (SAM 85) reveal that MgSiO(3) perovskite transforms from the orthorhombic Pbnm symmetry to another perovskite-type structure above 600 kelvin (K) at pressures of 7.3 gigapascals; the apparent volume increase across the transition is 0.7%. Unit-cell volume increased linearly with temperature, both below (1.4...

Phase separation , thermal history and magnetic behaviour of Sr doped

High-resolution transmission electron microscopy observations and magnetic ac susceptibility measurements have been carried out to study the changes in the magnetic properties of La1−xSrxCoO3 samples (x 0.3) processed at different annealing temperatures, ranging from 1273 to 1573 K. Although neutron diffraction excludes the coexistence of distinct phases with different chemical composition, roo...

Phase transitions and thermal expansion in pyroelectric energy conversion

This paper elucidates dynamic effects of phase transitions and thermal expansion on pyroelectric energy conversion. The Olsen cycle was performed on [001]-oriented 0:72PbMg1=3Nb2=3O30:28PbTiO3 (PMN-28PT) single crystals at different frequencies with electric field cycled between 0.2 and 0.75 MV/m and temperature between 22 and 140 C. The measured energy density more than doubled as frequency in...