| 提要文摘： | 本书内容包括：Radiation is everywhere. In this book， we are concerned with ionizing radiation， i.e. radiation that can ionize ordinary atoms. Translated into energies this corresponds to a， p， or y rays with energies larger than， say， 30eV. Almost everything is radioactive. Radiation emerges from the soil， it is in the air， and our pla is constantly bombarded with energetic cosmic radiation. Even the human body is radioactive：about 9000 decays of unstable nuclei occur per second in the human body. In the early days of the Earth， when our pla was formed from the debris of the proto-solar system， the radiation level was even higher. One can assume that the origin and development oflif. |
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