| 翻訳と辞書 |
yttrium
Yttrium is a chemical element with symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and it has often been classified as a "rare earth element".〔 Yttrium is almost always found combined with the lanthanides in rare earth minerals and is never found in nature as a free element. Its only stable isotope, 89Y, is also its only naturally occurring isotope.
In 1787, Carl Axel Arrhenius found a new mineral near Ytterby in Sweden and named it ''ytterbite'', after the village. Johan Gadolin discovered yttrium's oxide in Arrhenius' sample in 1789,〔 and Anders Gustaf Ekeberg named the new oxide ''yttria''. Elemental yttrium was first isolated in 1828 by Friedrich Wöhler.〔
The most important use of yttrium is in making phosphors, particularly the red phosphors used in television set cathode ray tube (CRT) displays and in LEDs.〔 It is also used in the production of electrodes, electrolytes, electronic filters, lasers and superconductors; various medical applications; and the tracing of various materials to enhance their properties. Yttrium has no known biological role, and exposure to yttrium compounds can cause lung disease in humans.〔
==Characteristics==
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
■ウィキペディアで「yttrium」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|