100px|A disc of californium metal
Californium is the radioactive metallic chemical element with atomic
number 98. It was first produced in 1950 by bombarding curium with
alpha particles at the University of California, Berkeley. The element
was named for California and the University of California. Two
crystalline forms exist for californium under normal pressure, and a
third exists at high pressure. Compounds of californium are dominated
by a chemical form of the element, designated californium(III), that
can participate in three chemical bonds. The most stable of
californium's twenty known isotopes is californium-251, which has a
half-life of 898 years; this short half-life means the element is not
found in the Earth's crust. Californium-252, whose half-life is
2.645 years, is the most common isotope used. Californium can be used
to help start up nuclear reactors, and is employed as a source of
neutrons when studying materials with neutron diffraction and neutron
spectroscopy. It can also be used in nuclear synthesis of higher mass
elements; ununoctium was synthesized by bombarding californium-249
atoms with calcium-48 ions. Use of californium must take into account
radiological concerns and the element's ability to disrupt the
formation of red blood cells by bio-accumulating in skeletal tissue.
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<http://en.wikipedia.org/wiki/Californium>
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Today's selected anniversaries:
365:
A large earthquake that struck near Crete and its subsequent tsunami
caused widespread destruction throughout the eastern Mediterranean
region.
<http://en.wikipedia.org/wiki/365_Crete_earthquake>
1865:
In one of the few recorded instances of a "quick draw" gun duel in the
American Old West, Wild Bill Hickok shot and killed Davis Tutt over a
poker debt.
<http://en.wikipedia.org/wiki/Wild_Bill_Hickok_%E2%80%93_Davis_Tutt_shootout>
1954:
First Indochina War: The Vietnamese Demilitarized Zone was established
at the Geneva Conference, partitioning Vietnam along the 17th parallel
north into two zones: North Vietnam led by Ho Chi Minh and South
Vietnam under Bao Dai.
<http://en.wikipedia.org/wiki/Geneva_Conference_%281954%29>
1969:
During the Apollo 11 mission, Neil Armstrong and Buzz Aldrin became
the first humans to walk on the Moon.
<http://en.wikipedia.org/wiki/Neil_Armstrong>
1970:
The Aswan High Dam in Egypt was completed after 11 years of
construction.
<http://en.wikipedia.org/wiki/Aswan_Dam>
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Wiktionary's word of the day:
charlady (n):
(chiefly archaic or historical) A woman whose professional occupation
is to clean houses; a cleaning-lady
<http://en.wiktionary.org/wiki/charlady>
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Wikiquote quote of the day:
Today is only one day in all the days that will ever be. But what will
happen in all the other days that ever come can depend on what you do
today. It's been that way all this year. It's been that way so many
times. All of war is that way.
--Ernest Hemingway
<http://en.wikiquote.org/wiki/Ernest_Hemingway>