back scatter beta gauge

例句：

1. 1. The backscatter beta gauge is usedto detect the presence of radioactive materialsin the environment.
   背散射β测量仪用于探测环境中放射性物质的存在。
2. 2. The backscatter beta gauge was used to monitor theradiation levels in the area.
   背散射β测量仪被用来监测该地区的辐射水平。
3. 3. The backscatter beta gauge was usedto study the behavior of particles in theatmosphere.
   背散射β测量仪被用来研究大气中粒子的行为。