Assertion: boron | /r/HasProperty | added
Facets:
value: usually
type: DEGREE
Source sentences:
text: Glass is more solid and heat resistant when boron is added, and glass fibres are applied as insulation.
text: University researchers have found yield increases ranging from 9 to 37 bushels of corn per acre where boron was added.
text: Boron is usually added when you need the hardness of a heat treated steel part to extend deep below the surface.