Search results
Results From The WOW.Com Content Network
The 238 U decay chain contributes six electron anti-neutrinos per 238 U nucleus (one per beta decay), resulting in a large detectable geoneutrino signal when decays occur within the Earth. [3] The decay of 238 U to daughter isotopes is extensively used in radiometric dating, particularly for material older than approximately 1 million years.
The 4n+2 chain of uranium-238 is called the "uranium series" or "radium series". Beginning with naturally occurring uranium-238, this series includes the following elements: astatine, bismuth, lead, mercury, polonium, protactinium, radium, radon, thallium, and thorium. All are present, at least transiently, in any natural uranium-containing ...
The decay chain of uranium-238 to uranium-234 and eventually lead-206 involves emission of eight alpha particles in a time (hundreds of thousands of years) short compared to the half-life of 238 U, so that a sample of 238 U in equilibrium with its decay products (as in natural uranium ore) will have eight times the alpha activity of 238 U alone.
The decay-chain of uranium-238, which contains radium-226 as an intermediate decay product. 226 Ra occurs in the decay chain of uranium-238 (238 U), which is the most common naturally occurring isotope of uranium. It undergoes alpha decay to radon-222, which is also radioactive; the decay chain ultimately terminates at lead-206.
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha, beta, and gamma decay.
Radon-222 (222 Rn, Rn-222, historically radium emanation or radon) is the most stable isotope of radon, with a half-life of approximately 3.8 days. It is transient in the decay chain of primordial uranium-238 and is the immediate decay product of radium-226.
Thirty-nine radioactive isotopes have been characterized, with mass numbers ranging from 193 to 231. [39] [40] Six of them, from 217 to 222 inclusive, occur naturally. The most stable isotope is 222 Rn (half-life 3.82 days), which is a decay product of 226 Ra, the latter being itself a decay product of 238 U. [41]
The tailings contain mainly decay products from the decay chain involving Uranium-238. [1] Uranium tailings contain over a dozen radioactive nuclides, which are the primary hazard posed by the tailings. The most important of these are thorium-230, radium-226, radon-222 (radon gas) and the daughter isotopes of radon decay, including polonium-210.