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- natural radioactivity background 天然放射性本底
- Two test methods, natural radioactive background method and decay method, used to verify the detection limit of radioactive aerosol monitors are studied. 两种方法不仅可检测监测仪的探测限,而且对各种监测仪探测限指标的物理意义能给以正确判断。
- He has a strong political background. 他有强大的政治背景。
- That incessant background music gets on my nerves. 那没完没了的背景音乐令我非常烦恼！
- Relating to or caused by radioactivity. 放射产生的关于放射性的或由放射性引起的
- He has a working-class background. 他是工人阶级出身。
- Get the fall in the background, will you? 把瀑布拍进背景中去好吗？
- A background accompaniment, as for a performer. 伴奏为一个演奏者配音伴奏
- A damaged reactor leaking radioactivity into the atmosphere. 一座损坏的反应堆向大气中泄露出发射性物质
- She came from a privileged background. 她出身於特权阶层。
- We have to learn to control radioactivity. 我们必须学会控制放射能。
- He came from an impoverished background. 他出身贫寒。
- This book gives the background of the Civil War. 这本书叙述了南北战争的背景。
- Other motives may have lurked in the background. 这后面可能隐藏着其它动机。
- He was lurking slyly in the background. 他狡猾地躲在背後活动。
- radioactivity background 放射性本底
- Her own particular chip on the shoulder was her poor background. 她感到怨恨的特有原因是她的背景不好。
- He stayed in the background to escape from the public attention. 他呆在幕后为了避开公众的注意。
- Some rare metals have radioactivity. 某些稀有金属具有放射性。
- Overburden had concealed the radioactivity. 覆盖层屏蔽掉了放射性。
