欧美日韩在线免费观看,久久精品黄色,国产在线精品视频,97免费中文视频在线观看,亚洲综合av一区

Nb

鈮1.jpg  


鈮2.jpg  


鈮3.jpg




Introduction
Purity:99.95%
Shape:Block,   Columnar
Appearance:grey   metal
Melting   Point:2468℃
Density:   8.57g/cm3


Scan and pay attention to the public number