id	keyword
brj-22852	friction
brj-22852	content
brj-22852	contact
brj-22852	pinecones
brj-22852	coefficient
brj-22852	friction coefficient
brj-22852	water
brj-22852	et al
brj-22852	material
brj-22852	test
brj-22852	results
brj-22852	water content
brj-22852	moisture