Progress report on programs in target research and in accelerator research.

A study was conducted on the elution behavior of curium (III), americium (III), plutonium (III), actinium (III), plutonium (IV), neptunium (IV), uranium (IV), thorium (IV), neptunium (V), plutonium (VI), uranium (VI), lanthanum (III), cerium (III), europium (III), ytterbium (III), ytterium (III), strontium (II), barium (II), radium (II), cesium (I) with 3.2 M, 6.2 M, and 12.2 M HCI solutions from Dower-50 cation exchange resin columns. These elutions show that in high concentrations of hydrochloric acid the actinides form complex ions with chloride ion to a much greater extent than the lanthanides. In order to explain these results, a partial covalent character may be ascribed to the bonding in the transuranium complex ions. It is shown that a reasonable structure for such covalent bonding involves hybridization of the 5g-ortibals in the actinide elements.