nanoparticles being incorporated into the BiFeO3nanoparticles. An exchange bias was observed before and after annealing that cannot be attributed to a structure that includes BiFeO3. It is likely to arise from magnetite and maghemite cores with spin-disordered shells.
Young Stellar Populations,In: Drissen Laurent, Robert Carmelle, St-Louis Nicole, Moffat Anthony F. J (eds.), Four Decades of Research on Massive Stars 465 pp. 392-397 Astronomical Society of the Pacific
study in the ultraviolet light because of their massive stars. I will present magnitude
and color simulations of young stellar populations in order to characterize their age,
metallicity, initial mass function, and star formation rate and history. These simulations
take into account the filters available with the Ultraviolet Imaging Telescope.
films prepared by ion beam sputtering,International Journal of Nanotechnology 14 (1-6) pp. pp 56-65 Inderscience Enterprises Ltd
sputtering followed by thermal annealing in a partial oxygen atmosphere.
The annealed films were found to be nanocrystalline, with an average particle
size of 11 nm for BiFeO3 and 8 nm for BiCrO3. The saturation moment per
formula unit is 0.39 µB for BiFeO3 which is significantly greater than that
found in bulk BiFeO3 (0.02 µB). A similar enhancement was also found in
previous studies of BiFeO3 nanoparticles where the nanoparticle size was
small. However, no large enhancement of the saturation moment per formula
unit was identified for the annealed BiCrO3 films. The annealed BiFeO3 films
displayed superparamagnetic behaviour and the particle size estimated from the
blocking temperature is comparable to that estimated from the X-ray diffraction
data. Our results show that sputtering and oxygen annealing is a method that
can be used to make nanocrystalline BiFeO3 and BiCrO3 films.