| 1. | How does natural radiation enter our body through the biosphere 天然放射性物质是怎样经过生物圈进入人体? |
| 2. | Article 4 the provisions of the act do not apply to naturally occurring radioactive material , background radiation , and their exposure herein 第4条天然放射性物质、背景辐射及其所造成之曝露,不适用本法之规定。 |
| 3. | Trace amounts of natural radioactive materials , such as uranium , thorium and potassium with half - lives of up to one billion years , exist in soil 泥土中含有微量的铀、钍和钾等天然放射性物质,这些放射性同位素的半衰期可以长达10亿年。 |
| 4. | Trace amounts of natural radioactive materials , such as uranium , thorium and potassium with half - lives of up to one billion years , exist in soil 泥土中含有微量的铀、钍和钾等天然放射性物质,这些放射性同位素的半衰期可以长达10亿年。 |
| 5. | Natural radiation comes from cosmic rays from outer space and naturally occurring radioactive materials that exist in food , air and our natural habitat 我们接触到的天然辐射包括来自外太空的宇宙射线及存在于食物空气及居住环境的天然放射性物质等。 |
| 6. | Natural radiation comes from cosmic rays from outer space and naturally occurring radioactive materials that exist in food , air and our natural habitat 我们接触到的天然辐射包括来自外太空的宇宙射线及存在于食物、空气及居住环境的天然放射性物质等。 |
| 7. | Antiquities can be dated by measuring their natural radioactivity . popular techniques include " carbon - 14 dating " and " thermoluminescence dating " . they are useful tools in geological , anthropological and archaeological researches 透过量度古物内天然放射性物质的浓度,我们可以鉴定古物所属的年代,常用的技术包括碳- 14定年法和热释光定年法,对地质学人类学及考古学的研究都有莫大的帮助。 |
| 8. | Antiquities can be dated by measuring their natural radioactivity . popular techniques include " carbon - 14 dating " and " thermoluminescence dating " . they are useful tools in geological , anthropological and archaeological researches . carbon - 14 is produced when cosmic rays bombard the atmosphere 透过量度古物内天然放射性物质的浓度,我们可以鉴定古物所属的年代,常用的技术包括碳- 14定年法和热释光定年法,对地质学、人类学及考古学的研究都有莫大的帮助。 |
| 9. | Antiquities can be dated by measuring their natural radioactivity . popular techniques include " carbon - 14 dating " and " thermoluminescence dating " . they are useful tools in geological , anthropological and archaeological researches . carbon - 14 is produced when cosmic rays bombard the atmosphere 透过量度古物内天然放射性物质的浓度,我们可以鉴定古物所属的年代,常用的技术包括碳- 14定年法和热释光定年法,对地质学、人类学及考古学的研究都有莫大的帮助。 |