The heat capacity of specially prepared orthorhombic sulfur has been measured in a low-temperature adiabatic calorimeter. Measurements from T ~ 6 K to near the melting temperature transition at Tfug = 388.36 K are reported for equilibrium sulfur: for the orthorhombic modification from T » 6 K to the temperature of the orthorhombic-to-monoclinic transition Ttrg = 368.3 K, and for the monoclinic ...

Raman spectroscopy demonstrates that ,5 nm dimension HfxZr1−xO2 nanocrystals prepared by a nonhydrolytic sol-gel synthesis method are solid solutions of hafnia and zirconia, with no discernable segregation within the individual nanoparticles. Zirconia-rich particles are tetragonal and ensembles of hafnia-rich particles show mixed tetragonal/monoclinic phases. Sintering at 1200 °C produces large...

Zirconia femoral heads retrieved from patients after different implantation periods (up to 13 years) were analysed using vertical scanning interferometry, atomic force microscopy and Raman microspectroscopy. A range of topographical and compositional changes on the surface of the retrievals are reported in this work. The study revealed that changes in roughness are the result of a combination o...