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Meaning of Half-life | Babel Free

Noun CEFR B2
/ˈhæfˌlaɪf/

Definitions

  1. The time required for half the nuclei in a sample of an isotope to undergo radioactive decay.
  2. In a chemical reaction, the time required for the concentration of a reactant to fall from a chosen value to half that value.
    physical
  3. The time it takes for a substance (drug, radioactive nuclide, or other) to lose half of its pharmacological, physiologic, or radiological activity.
  4. The amount of time it takes for an idea or a fashion to lose half of its influential power.

Equivalents

Examples

“"The guy that just left—what's he got in his lungs?" / "Well, I'm not very sure. But the two best candidates are uranium-233 and plutonium-239, one or both." / "They're in his bones too, aren't they?" / "Yeah, they're both boneseekers. And they've got half-lives of one hundred sixty-two thousand and twenty-four thousand years respectively. So they stay hot for a long time."”
“O₂^(•−) and OH^• are highly unstable (half-life at the level of microseconds and nanoseconds, respectively) and cannot cross membrane, while H₂O₂, though not a free radical but a ROS, is relatively stable (half-life around 1 ms) (Møller et al. 2007) and can cross membranes through aquaporins.”
“For nonporous surfaces such as steel, in a dark and low-humidity environment, the CCP virus has an 18-hour half-life—the time required for it to decrease by half , according to the researchers' findings.”
“Most books of scholarship have surprisingly short intellectual half-lives during which they make a difference"”

CEFR level

B2
Upper Intermediate
This word is part of the CEFR B2 vocabulary — upper intermediate level.

See also

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