U-238


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AcronymDefinition
U-238Uranium-238
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"Internationally, the deep alarm of officials associated with the discovery of U-238 was compounded earlier this year when a group of individuals was discovered attempting to smuggle Cesium-137, a highly radioactive isotope that is a waste product from nuclear reactors," Murinson added.
In a gas centrifuge the light molecules (U-235) are accumulated at the centre and the heavy molecules (U-238) at the periphery of the centrifuge.
The highspeed neutrons generated by fusion could split apart the u-238 atoms to generate fission, and the fission could generate lots of energy to help maintain the fusion, thus significantly reducing the amount of external energy input, and achieve the complete burning of nuclear fuel to avoid radioactive waste.
The first line of the table below shows 1,000 atoms of natural uranium split between 7 atoms of U-235 and 993 atoms of U-238.
For determining activity degree of elements such as U-238, Ra-226, Th-232, Cs-137, and K-40, we sent 4 soil samples to Iran's atomic energy agency laboratory (Jaber-ebn-Hayyan laboratory), and measured by HPGe Gamma spectrometer with germanium detector.
The natural Uranium (U-238) has to be enriched before using it as a fissile material to make a bomb.
It has other elements and other isotopes in it, notably U-238. U-238 isn't ordinarily very radioactive.
Most nuclear reactors today are light water reactors (LWR), cooled by water and fueled by uranium-238, or U-238 (the most common naturally occurring uranium isotope) and 4% to 5% U-235.
(5) Uranium in nature is 99.3% U-238 and 0.7% U-235; U-235 must be concentrated, or "enriched." Uranium enriched to 20% U-235 is termed highly enriched uranium, or HEU, but nuclear weapons typically use uranium enriched to 90% or so.
Sanders explains, "Depleted uranium is essentially U-238, the isotope after the fissionable isotope, U-235, has been extracted from uranium ore." DU has a half-life of 4.7 billion years.
Between the Gulf War and current wars, at least 2,700 tons of this particulated mutagenic waste (the 99 percent residual U-238 from our nuclear power facilities, provided at little or no cost to the weapons industry) has been dumped on Iraq and another 1,000 tons on Afghanistan (see www?.iacenter.org/depleted).
Natural uranium consists of two radioactive isotopes, U-235 and U-238, while only U-235 can split up with emission of energy.