12 research outputs found
Access to Health
Access to health is an often-overlooked aspect of the right to health. Without practical access, the right to health becomes an empty promise. International human rights conventions and declarations do not directly mention access to health, but the above comment on the International Covenant on Economic, Social, and Cultural Rights does address the issue
Tuning Exchange Bias in Core/Shell FeO/Fe<sub>3</sub>O<sub>4</sub> Nanoparticles
Monodisperse 35 nm FeO nanoparticles (NPs) were synthesized
and
oxidized in a dry air atmosphere into core/shell FeO/Fe<sub>3</sub>O<sub>4</sub> NPs with both FeO core and Fe<sub>3</sub>O<sub>4</sub> shell dimensions controlled by reaction temperature and time. Temperature-dependent
magnetic properties were studied on FeO/Fe<sub>3</sub>O<sub>4</sub> NPs obtained from the FeO NPs oxidized at 60 and 100 °C for
30 min. A large exchange bias (shift in the hysteresis loop) was observed
in these core/shell NPs. The relative dimensions of the core and shell
determine not only the coercivity and exchange field but also the
dominant reversal mechanism of the ferrimagnetic Fe<sub>3</sub>O<sub>4</sub> component. This is the first time demonstration of tuning
exchange bias and of controlling asymmetric magnetization reversal
in FeO/Fe<sub>3</sub>O<sub>4</sub> NPs with antiferromagnetic core
and ferrimagnetic shell