In the tables below ( except neptunium ), the historic names of the naturally occurring nuclides are also given.
42.
The same paper mentioned a release of 7.6 trillion becquerels of neptunium-239 about 1 milligram.
43.
The most stable state in solution is + 5, but the valence + 4 is preferred in solid neptunium compounds.
44.
Some known such compounds include the neptunyl dimer ?H 2 O and neptunium glycolate, both of which form green crystals.
45.
However, the oxides of plutonium and neptunium with the chemical formula AnO 2 and An 2 O 3 are well characterized.
46.
However, there are three naturally occurring radioactive isotopes of astatine produced via radioactive decay of uranium, neptunium, and plutonium.
47.
The contaminant plutonium-241 beta-decays to americium-241, which then alpha-decays to neptunium-237.
48.
Even at concentrations 7, more than 70 % of strontium and technetium are removed with up to 20 % of neptunium.
49.
Once in the environment, neptunium generally colloidal particulates, an effect that is enhanced when in soil with a high clay content.
50.
Finely divided neptunium metal presents a fire hazard because neptunium is pyrophoric; small grains will ignite spontaneously in air at room temperature.
