Because of sub - critical safety , fully using of the thorium - uranium resources and efficiency disposal high - radioactivity waste , this research has become the hot pot 因为具有次临界安全性、充分利用钍、铀资源和高放射性废物的处置三大优点，成为研究的热点。
I then thought that the greater activity of the natural minerals might be determined by the presence of a small quantity of a highly - radioactive material , different from uranium , thorium and the elements known at present 我随后想到天然矿石中较大的活性可能是因为其中含有少量的高放射性物质所致，这种物质不同于铀、钍或其他已知的任何元素。
In reality the proportion of the hypothetical element was far lower and it took several years to show unequivocally that pitchblende contains at least one highly - radioactive material which is a new element in the sense that chemistry attaches to the term 实际上这种假设中的元素的浓度要小得多，我们花了几年时间才明确无误地证明沥青铀矿物质中至少含有一种高放射性物质，在化学意义上这就是一种新元素。
