Search results
Results from the WOW.Com Content Network
In December 1901 and January 1902, at the direction of archaeologist Jacques de Morgan, Father Jean-Vincent Scheil, OP found a 2.25 meter (or 88.5 inch) tall basalt or diorite stele in three pieces inscribed with 4,130 lines of cuneiform law dictated by Hammurabi (c. 1792–1750 BC) of the First Babylonian Empire in the city of Shush, Iran.
The biological half-life of strontium in humans has variously been reported as from 14 to 600 days, [86] [87] 1,000 days, [88] 18 years, [89] 30 years [90] and, at an upper limit, 49 years. [91] The wide-ranging published biological half-life figures are explained by strontium's complex metabolism within the body.
Life insurance (or life assurance, especially in the Commonwealth of Nations) is a contract between an insurance policy holder and an insurer or assurer, where the insurer promises to pay a designated beneficiary a sum of money upon the death of an insured person.
The rubidium–strontium dating method (Rb–Sr) is a radiometric dating technique, used by scientists to determine the age of rocks and minerals from their content of specific isotopes of rubidium (87 Rb) and strontium (87 Sr, 86 Sr). One of the two naturally occurring isotopes of rubidium, 87 Rb, decays to 87 Sr with a half-life of 49.
Naturally occurring strontium is nonradioactive and nontoxic at levels normally found in the environment, but 90 Sr is a radiation hazard. [4] 90 Sr undergoes β − decay with a half-life of 28.79 years and a decay energy of 0.546 MeV distributed to an electron, an antineutrino, and the yttrium isotope 90 Y, which in turn undergoes β − decay with a half-life of 64 hours and a decay energy ...
The longest-lived of these isotopes, and the most relevantly studied, are 90 Sr with a half-life of 28.9 years, 85 Sr with a half-life of 64.853 days, and 89 Sr (89 Sr) with a half-life of 50.57 days. All other strontium isotopes have half-lives shorter than 50 days, most under 100 minutes.
Celestine (the IMA-accepted name) [6] or celestite [1] [7] [a] is a mineral consisting of strontium sulfate (Sr S O 4). The mineral is named for its occasional delicate blue color. Celestine and the carbonate mineral strontianite are the principal sources of the element strontium, commonly used in fireworks and in various metal alloys.
The element was eventually isolated by Sir Humphry Davy in 1808 by the electrolysis of a mixture containing strontium chloride and mercuric oxide, and announced by him in a lecture to the Royal Society on 30 June 1808. [8] In keeping with the naming of the other alkaline earths, he changed the name to strontium.