| Popis: |
The electromagnetic separations group at Oak Ridge National Laboratory (ORNL) has collected and purified isotopes for special purposes, including 46 Ca, 48 Ca, 182 W, 186 W, 33 S, 29 Si and 30 Si. Certain contaminants have been reduced to the ppb-range in some preparations. Experiences in preparing ∼ 10-g crystals of 48 CaF 2 and > 100-g cylinders of tungsten isotopes are given. The results of experimental ion collections on single crystals of copper and on various other substrates are presented. These collection techniques are applicable for preparation of specimens for diffusion studies, the formation of semiconductors, etc. Singly or doubly charged ions can be deposited with a considerable choice of ion velocity. In other preparations, actinide isotopes have been electrodeposited uniformly on a variety of metal forms. |
