【单选题】Which of the following is NOT true according to the poor electrical and thermal conduction property of ceramics?
A.
The valence electrons are tied up in bonds and are not free in ceramics
B.
Diamond which is classified as a ceramic has the highest thermal conductivity of any known material
C.
the oxide ceramic ReO3, has an electrical conductivity at room temperature similar to that of Cu
D.
the mixed oxide YBa2Cu3O7 has zero resistivity below 92℃
【单选题】According to Figure 1, which of the following state-ments best describes how the resistivity of the sandand gravel layer compares to the resistivity of the tilllayers? The resistivity measured in the ...
A.
lower than the resistivities measured in any of the till layers.
B.
higher than the resistivities measured in any of the till layers.
C.
the same as the resistivities measured in the sur-face sediments.
D.
lower than the resistivities measured in the bed-rock.
【单选题】If the IT0 and IT1 bits of the TCON register are , an interrupt will be generated on high to low transition, i.e. on thefallingpulse edge (only in that moment).
C.
high resistivity state