"metals"에 대한 검색 결과입니다. 검색 결과 보는 도중에 Tab 키를 누르시면 검색 창이 선택됩니다.
MeSH(Medical Subject Headings) 맞춤 검색 (http://www.nlm.nih.gov) 결과 : 1 페이지: 2
Metals, Rare Earth - 새창
A group of elements that include SCANDIUM; YTTRIUM; and the LANTHANOID SERIES ELEMENTS. Historically, the rare earth metals got their name from the fact that they were never found in their pure elemental form, but as an oxide. In addition they were very difficult to purify. They are not truly rare and comprise about 25% of the metals in the earth's crust.