Assertion: cathode | /r/HasProperty | treated with chemical
Facets:
value: with a low work function
type: OTHER
value: usually
type: TEMPORAL
value: in order to improve electron emission
type: PURPOSE
Source sentences:
text: In order to improve electron emission, cathodes are treated with chemicals, usually compounds of metals with a low work function.
text: To improve electron emission, cathodes are usually treated with chemicals, compounds of metals with a low work function.