マイトネリウム 化学特性,用途語,生産方法
解説
マイトネリウム，Mt．原子番号109の元素．電子配置[Rn]5f 146d77s2(推定)の周期表9族元素．周期表でイリジウムの下に位置する(エカイリジウム)．短寿命人工元素．質量数265～279の同位体核種がつくられている．268の同位体がもっとも長寿命で半減期21 ms．1982年8月，ドイツ・ダルムシュタットの重イオン研究所(GSI)で，209Bi を標的として 58Fe で衝撃して半減期1.7 ms でα崩壊する 266Mt 1原子が得られた．α崩壊を2回繰り返して 258Db になる．室温で固体の銀白色または灰色の金属とされる．命名はO. Hahn(ハーン)の共同研究者で，4回もノーベル賞候補にあげられたオーストリアの女性化学者L. Meitner(マイトナー)にちなむ．
性質
室温で固体の銀白色または灰色の金属とされる．命名はO.
物理的性質
Not many chemical and physical properties of Une (or Mt) are known, but it is artificiallyproduced by the basic process of combining the isotopes of two elements to produce a fewatoms of a heavier isotope in linear accelerators. In this case, the creation of a few atoms ofelement 109 involves a similar nuclear process of fusion as was used for element 108. Thereaction follows:
83Bi-209 +
26Fe-58 →
109Une-266 +
0n-1 (free neutron).
The most stable isotope of unnilennium is meitnerium-276, which has a half-life of about0.72 seconds. Une-276 decays into element 107 (Uns-272 or bohrium-272).
The melting point, boiling point, and density of unnilennium (meitneriumare unknown,as are many of its other chemical and physical properties.
同位体
There are five isotopes of unnilennium (meitnerium), ranging from Une-266 toUne-276, and with half-lives ranging from 1.7 milliseconds to 0.72 seconds.
名前の由来
Named for the Austrian scientist Lise Meitner.
来歴
On August 29, 1992, Element 109 was made and identified by physicists at the Heavy Ion Research Laboratory (G.S.I.), Darmstadt, Germany, by bombarding a target of
209Bi with accelerated nuclei of
58Fe. The production of Element 109 has been extremely small. It took a week of target bombardment (1011 nuclear encounters) to produce a single atom of 109. Oganessian and his team at Dubna in 1994 repeated the Darmstadt experiment using a tenfold irradiation dose. One fission event from seven alpha decays of 109 was observed, thus indirectly confirming the existence of isotope
266109. In August 1997, the IUPAC adopted the name meitnerium for this element, honoring L. Meitner. Four isotopes of meitnerium are now recognized.
使用
None, except for research purposes.
定義
meitnerium: Symbol Mt. A radioactivetransactinide element; a.n.109. It was first made in 1982 by Peter Armbruster and a team in Darmstadt, Germany, by bombarding bismuth-209 nuclei with iron-58 nuclei.Only a few atoms have ever been detected.
危険性
None, except for radiation, which is not much of a risk given that only a few atoms existin nuclear laboratories.
マイトネリウム 上流と下流の製品情報
原材料
準備製品