LR
LR
Lr
| an extraordinary or unusual thing, person, or event; an exceptional example or instance. |
| a gadget; dingus; thingumbob. |
L.R.
Based on the Random House Dictionary, © Random House, Inc. 2013.
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| lr | |
| —the internet domain name for | |
| Liberia | |
| Lr | |
| —the chemical symbol for | |
| lawrencium | |
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Lr
The symbol for the element lawrencium.
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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lawrencium  (lô-rěn'sē-əm) Pronunciation Key
Symbol Lr A synthetic, radioactive metallic element of the actinide series that is produced by bombarding californium with boron ions. Its most stable isotope is Lr 262 with a half-life of 3.6 hours. Atomic number 103. See Periodic Table. |
| Lr
The symbol for lawrencium. |
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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| Lr lawrencium |
LR
|
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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lr
(Lr), synthetic chemical element, the 14th member of the actinoid series of the periodic table, atomic number 103. Not occurring in nature, lawrencium (as the isotopes lawrencium-257, lawrencium-258, and lawrencium-259) was produced (1961) by Albert Ghiorso, T. Sikkeland, A.E. Larsh, and R.M. Latimer at the University of California, Berkeley, by bombarding a mixture of the longest-lived isotopes of californium (atomic number 98) with boron ions (atomic number 5) accelerated in a heavy-ion linear accelerator. A team of Soviet scientists at the Joint Institute for Nuclear Research in Dubna discovered (1965) lawrencium-256 (35-second half-life), which the Berkeley group used to show that lawrencium behaves more like the tripositive elements in the actinide series than like predominantly dipositive nobelium (atomic number 102).
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