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11
CH1012
CERAMICS III.h
Superconducting Ceramics
show the unusual property of
having virtually zero resistance
at the relatively high Tc of > 77K.
(Tc = superconducting transition T)
• The YBa2Cu3O7 structure (95K)
shown has Cu chains where Cu
has the oxidation state of 2.33.
• The cost of He(l) is $20/L (<77K)
whereas N2(l) is $1 (>77K). This
means there is much scope for
using high-Tc ceramics in power transmission.
e-
Japanese Maglev train running on HTS magnet made using HTS wire.
Bismuth based superconductor using freezer rather than liquid N2 (or liquid He)
Cu donates single electron to O with conductivity 104 times greater in horizontal direction.