Electrical properties of Ca
3–
x
Sm
x
Co
4
O
9+δ
ceramics prepared under magnetic field
Qu Xiu-Rong
1, 2, †
, Xu Yan-Yan
1
, Lü Shu-Chen
1
, Hu Jian-Min
1
Changes of ln(
T
/
ρ
) with 1000/
T
for Sm-doped bulk materials.
