| Agent Name |
Promethium |
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| CAS Number |
7440-12-2; 14380-75-7 ( Pm-147) |
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| Formula |
Pm |
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| Major Category |
Metals |
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| Category |
Rare Earth Metals |
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| Description |
Solid metal; [Merck Index] |
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| Sources/Uses |
Promethium is present in rare earth minerals Pm-147 in minute quantities (< 10E-19 %) as a result of cosmic ray reactions and spontaneous fission of U-238. [Ullmann] Used in nuclear-powered batteries, thickness gauges, luminous compounds, and portable x-ray sources; [Merck Index] |
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| Comments |
All isotopes are radioactive (mass numbers = 132-155); Pm-145 has the longest half-life at 17.7 years, an alpha emitter; Present at low levels in uranium ores; [Merck Index] Pm-147 with a half-life of 2.6 years is the most useful isotope. Pm-145 has the longest half-life; it has a specific activity of 940 Ci/g. See "RARE EARTH METALS." See "Radiation, Ionizing." |
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| Reference Link |
http://periodic.lanl.gov/elements/61.html |
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| Exposure Assessment |
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| Explanatory Notes |
mp = 1080 deg C; [Merck Index] |
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| Links to Other NLM Databases |
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