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- 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。
- Radioactive ray is material thing. 放射线是实际的物质。
- 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！
- Radium and uranium are radioactive elements. 镭和铀是放射性元素。
- He has a working-class background. 他是工人阶级出身。
- A certain discharge of possible radioactive effluent. 一定量的可能有放射性的废水。
- 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
- natural radioactivity background 天然放射性本底
- She came from a privileged background. 她出身於特权阶层。
- 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。
- A radioactive isotope of carbon, especially carbon 14. 放射性碳碳的一种放射性同位素，尤指碳14。
- 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。
- A naturally occurring or artificially produced radioactive element. 放射性元素自然产生或人为制造的放射性元素
- A radioactive compound used in radiotherapy or diagnosis. 放射性药剂一种用于放射性治疗或诊断的放射性化合物
- 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。
- The immediate product of the radioactive decay of an element. 继承元素某种元素放射性衰变的直接产物
