UNC LASSIFIED ANALYTICAL PROCEDURES FOR DETERMINATION OF SR®°° BY SEPARATION AND COUNTING OF y9° 1. After the sample on the brass holder has been counted for total strontium and has reached equilibrium, it may be used for Y®° separation. 2. Countthe sample and record data. 3. Remove the sample from the brass holder. Wash the holder with about 25 ml of water. Allow washings to fall into beaker with the bulk of the paper. 4. Bring to a boil and filter thru No. 41 paper into a 3 ml platinum dish. Wash the beaker and paper with avoroximate- ly 15 ml more of water. 5S. 6. Evaporate to dryness on a sand bath. Pick up the residue with approximately 5 drops of HCl. fer to a beaker with water. 10 mg of lanthanum carrier. 8 activity). 7. Add approximately 20 ml of HF and evaporate to dryness again. Add (This carrier must have negligible Bring to a boil and adjust pH to 6-7. Allow to stand for about 15 minutes and filter thru a l~1/8 glass fiber paper. brass holder. Trans- Bring volume to about 50 ml. Cover with pliofilm and count. Place on 8. Record time that filtration was completed. counting date and counting time. Count and record 9. Observe decay by counting at approximately 3-day intervals for a period of about 12 days. The procedure was tessed by measuring the recovery of Y°* added to solutions containing 20 me of Sr as the nitrate. The recoveries found with either paper or glass fiber filters were 94-99%. eee (0 UNC LASS IFIaD