Barium compounds 1 Barium metallography Calcination 1 Calcination temperature 1 Cerium compounds 1 Chelation 1 Elemental compositions 1 Energy dispersive x-ray 1 Fluorescence spectroscopy 1 Modified sol-gel method 1 Morphology 1 Particle size 1 Particle size analysis 1 Particle size analyzers 1 Scanning electron microscopy 1 Sol-gel process 1 Sol-gel technique 1 Sol-gels 1 Stoichiometric compositions 1 X rays 1 X-ray fluorescence spectroscopy 1 Zirconium compounds 1 Zirconium metallography 1