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The most important isotope is astatine-211, the only one in commercial use. To produce the bismuth target, the metal is sputtered onto a gold, copper, or aluminium surface at 50 to 100 milligrams per square centimeter. Bismuth oxide can be used instead; this is forcibly fused with a copper plate. [126]
Astatine can replace a hydrogen atom in benzene to form astatobenzene C 6 H 5 At; this may be oxidized to C 6 H 5 AtCl 2 by chlorine. By treating this compound with an alkaline solution of hypochlorite, C 6 H 5 AtO 2 can be produced. [31] Astatine-labelled iodine reagents have been used to synthesise RAt, RAtCl 2, R 2 AtCl, and RAtO 2 (R ...
Organoastatine chemistry describes the synthesis and properties of organoastatine compounds, chemical compounds containing a carbon to astatine chemical bond. Astatine is extremely radioactive, with the longest-lived isotope (210 At) having a half-life of only 8.1 hours. Consequently, organoastatine chemistry can only be studied by tracer ...
Astatine has 23 nuclear isomers (nuclei with one or more nucleons – protons or neutrons – in an excited state). A nuclear isomer may also be called a " meta -state"; this means the system has more internal energy than the " ground state " (the state with the lowest possible internal energy), making the former likely to decay into the latter.
Iron is stored in many organisms in the form of ferritin, which is a ferrous oxide encased in a solubilizing protein sheath. [ 10 ] Species of bacteria , including Shewanella oneidensis , Geobacter sulfurreducens and Geobacter metallireducens , use iron oxides as terminal electron acceptors .
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Astatine-229 This page was last edited on 23 January 2021, at 05:47 (UTC). Text is available under the Creative Commons Attribution-ShareAlike 4.0 License ...
Sodium astatide solution has been prepared by distilling astatine from the bismuth alpha-ray target where it was prepared, dissolving in sodium bicarbonate solution, and reducing At + and At 3+ ions with ascorbic acid.