n.锕(放射性化学元素)

Actinium is a radioactive element with the atomic number 89 and symbol Ac.
铀是原子序数为89并以Ac为符号的放射性元素。
In nuclear medicine, actinium-225 is used as a source for alpha particle therapy.
在核医学中，锕-225被用作阿尔法粒子疗法的源。
Actinium is not found naturally in significant quantities due to its short half-life.
由于锕的半衰期较短，自然界中并未发现其大量存在。
The discovery of actinium marked an important milestone in the development of radiochemistry.
锔的发现标志着放射化学发展的一个重要里程碑。
Actinium oxide (AcO) is a compound used in research to study the properties of actinium.
锕氧化物（AcO）是一种用于研究锕性质的化合物。
Due to its high reactivity, handling of actinium requires extreme caution.
由于锕的高度反应性，对其进行操作需要极为小心。
The radioactive decay series that starts with actinium-235 ultimately leads to a stable isotope of lead.
开始于锕-235的放射性衰变系列最终会形成稳定的铅同位素。
Actinium can be produced artificially by bombarding thorium or uranium targets with neutrons in a nuclear reactor.
锕可以通过在核反应器中使用中子轰击钍或铀靶人工合成。
The chemical behavior of actinium resembles that of the lanthanide series, making it difficult to separate from other elements in its ore.
锕的化学性质与镧系元素相似，这使得它在矿石中的分离变得困难。
Actinium-227 decays into francium-223, which is another rare radioactive element with only a few grams existing on Earth at any given time.
锕-227衰变为钫-223，这是一种同样稀有且在地球上的任何时刻仅存在几克的放射性元素。