???Ta, Tantalum
Tantalum is a chemical element with the symbol Ta and atomic number 73. A rare, hard, blue-gray, lustrous transition metal, tantalum is highly corrosion resistant.
?? ??Ta??? ? ?1.72416?2.075176???. ??? ?? ??? ? ??? ?????. ??? ????? ? ?? ?? '??'? ???? ?? ??? ??? ? ????.
Refractive Index Reference - Sopra Material Database
??? ???? ???? ???, ??? ?? ??? ????? ????.
?? ?? ??????? ?????? ?? ??? ? ?? ? ?? ??? ??: