1·The water contains two of the least dangerous radioactive materials now in the news - radioactive nitrogen and tritium.
冷却水含有新闻报道的两种危险程度最低的放射性物质——放射氮和放射氚。
2·Although such a cloud would pose virtually no threat while in the upper atmosphere, the fallout at the ground of radioactive particles from it should be a concern for any monitoring authority.
虽然这种云在高层大气中几乎不构成任何威胁，但是它在地面散发出的放射粒子的余波应该是任何监管机构所关注的。
3·In Oslo, callers were on the phone to the State Institute for Radiation Hygiene afternews reports told of an invisible radioactive cloud over the most denselypopulated part of Norway.
在奥斯陆（译注：挪威首都），新闻中播报了放射云正在挪威人口最稠密地区上空的消息以后，挪威辐射卫生研究所的电话被打爆了。
4·The different radioactive materials being reported at the nuclear accidents in Japan range from relatively benign to extremely worrisome.
日本核事故中报道的不同放射物质从相对良性的到让人极其担忧的都有。
5·The solid fuel pellet (a ceramic oxide matrix) is the first barrier that retains many of the radioactive fission products produced by the fission process.
固体的燃料弹（陶式氧化物母体）是第一道防护，隔开裂变过程中产生的裂变放射。