| 摘要 |
A beam of accelerated charged particles irradiates an arsenide target, such as gallium arsenide or aluminum arsenide, to produce radioisotopes of selenium and other radionuclides. The irradiated target is placed in a niobium, tantalum, or graphite vessel and inserted into a tube. Metallic reagents consisting of an alloy of iron, nickel, and chromium (stainless steel) or metallic aluminum are mixed with the target material. The target is then heated to 1000-1100 DEG C. The metallic reagents prevent arsenic sublimation, destroy the crystalline structure of arsenide target, and remove other impurities, such as zinc-65. The target is then heated a second time to about 1300 DEG C. causing the selenium-72 to sublime and be deposited on a cooler wall of the tube or on a catcher foil surface. The deposited selenium-72 is recovered from the tube or foil.
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