| 1. | Overburden had concealed the radioactivity .
覆盖层屏蔽掉了放射性。 |
| 2. | Natural radioactivity contains a store of valuable information .
天然放射性包含着许多有价值的信息。 |
| 3. | Radioactivity is found on both sides of the failure plane in all cases .
破断面的任何一侧都发现有放射性。 |
| 4. | This example illustrates the great sensitivity of the radioactivity method .
这个例子说明了放射性方法很灵敏。 |
| 5. | Radioactivity is the ejection of particles or radiation from the nucleus .
放射性是原子从核中射出粒子或辐射的现象。 |
| 6. | The atomic bomb is characterized by the grave injuries caused by radioactivity .
原子弹具有由辐射引起严重损伤的特点。 |
| 7. | The radioactivity of a sample is defined to be the number of disintegrations per unit time .
样品的放射性定义为每单位时间的蜕变数目。 |
| 8. | At the surface, radioactivity of the conglomerates is locally as high as 30 x background .
在地表，砾岩的局部地段的放射性高达30倍本底值。 |
| 9. | In practice it would be possible to measure radioactivity one thousand fold less than this .
在实际上，比这个值小一千倍的放射也有可能测定。 |
| 10. | At the same time radioactivity injured the inner tissues of the skin and formed keloids on the surface of the skin .
辐射力同时破坏组织，在表皮上形成瘢痕。 |
