cobalt 60

例句：

1. 1.The cobalt 60 was used in the medical imaging equipment.
   钴60被用于医疗成像设备中。
2. 2. The cobalt 60 is a rare and valuable mineral.
   钴60是一种稀有且有价值的矿物。
3. 3. The cobalt 60 is essential for the production of nuclear reactors.
   钴60是核反应堆生产所必需的。