Matched context for impurity and ammonia

The page lists matched contexts for impurity and ammonia.

Share - impurity	Share - ammonia	Phrase
16.54%	1.96%	remove {impurity or ammonia} [perform operation]
3.81%	2.34%	gaseous [state] {impurity or ammonia}
3.94%	1.41%	{impurity or ammonia} removal
2.18%	1.34%	liquid [state] {impurity or ammonia}