| 释义 |
Definition of half-life in English: half-lifenoun 1The time taken for the radioactivity of a specified isotope to fall to half its original value. iodine-131 has a half-life of 8.1 days Example sentencesExamples - The small, lead-shielded canisters contain pellets or a fine powder of caesium 137, which emits powerful gamma radiation with a half-life of 30 years.
- Tritium is radioactive, with a half-life of 12.26 years.
- Radioactive depleted uranium has a half-life of 4500 million years.
- In addition, the plants would produce 7,313 tonnes of highly radioactive waste with a half-life of 24,000 years.
- The FDA recommends keeping a fourteen-day supply on hand; radioactive iodine has a half-life of eight days.
- 1.1 The time required for any specified property (e.g. the concentration of a substance in the body) to decrease by half.
Example sentencesExamples - It stays in the body for a lifetime, it has a half-life of 28, 29 years and it gets into the bone, it's taken up just like calcium.
- This constitutes the main long-term threat in the area as the chemical has a half-life of 30 years.
- Frova may represent an important advancement in the treatment of migraine headache as no other currently marketed treatment has a half-life of more than six hours.
- Prealbumin, also known as transthyretin, has a half-life of only 1 to 2 days.
- At age 18, caffeine has a half-life of 4.5 hours, which increases with age.
Definition of half-life in US English: half-lifenounˈhæf ˌlaɪfˈhaf ˌlīf 1The time taken for the radioactivity of a specified isotope to fall to half its original value. iodine-131 has a half-life of 8.1 days Example sentencesExamples - Radioactive depleted uranium has a half-life of 4500 million years.
- The FDA recommends keeping a fourteen-day supply on hand; radioactive iodine has a half-life of eight days.
- In addition, the plants would produce 7,313 tonnes of highly radioactive waste with a half-life of 24,000 years.
- Tritium is radioactive, with a half-life of 12.26 years.
- The small, lead-shielded canisters contain pellets or a fine powder of caesium 137, which emits powerful gamma radiation with a half-life of 30 years.
- 1.1 The time required for any specified property (e.g. the concentration of a substance in the body) to decrease by half.
Example sentencesExamples - It stays in the body for a lifetime, it has a half-life of 28, 29 years and it gets into the bone, it's taken up just like calcium.
- At age 18, caffeine has a half-life of 4.5 hours, which increases with age.
- Prealbumin, also known as transthyretin, has a half-life of only 1 to 2 days.
- Frova may represent an important advancement in the treatment of migraine headache as no other currently marketed treatment has a half-life of more than six hours.
- This constitutes the main long-term threat in the area as the chemical has a half-life of 30 years.
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