Nb vs atomic number 41

Nb and atomic number 41 both are nouns.

Word	Noun	Adjective	Verb	Adverb
Nb	Yes	No	No	No
atomic number 41	Yes	No	No	No

As nouns, Nb and atomic number 41 are synonyms defined as:

Nb and atomic number 41: a soft grey ductile metallic element used in alloys; occurs in niobite; formerly called columbium

Other synonyms of Nb include niobium.

Nb (noun)	atomic number 41 (noun)
a soft grey ductile metallic element used in alloys; occurs in niobite; formerly called columbium	a soft grey ductile metallic element used in alloys; occurs in niobite; formerly called columbium