Analysis Results for Activated Packard 21-635 PPO



Zelimir Djurcic and Andreas Piepke
University of Alabama
(Status 7/17/2001)


We describe the analysis of the activated PPO sample Packard batch 21-635 (rejected) UA32 and UA33. As this PPO batch has not been used in KamLAND we have only performed a short 1 hour irradiation for the sake of a speedy analysis. The activated sample was not subjected to ion exchange. We are reporting the most prominent side activities to compare with a similar analysis done with Packard PPO batch 21-634 in March 2001.
After activation the sample has been removed from the irradiation vials by means of acid digestion. No further separation of activities was done. The conversion of measured activities into chemical concentration assumes an extraction efficiency of 100%.
In the table below we list the activities in [Bq] determined for that sample. Irradiation time, shipping delay and sample mass are given as well. The errors quoted are statistical only. We estimate the systematic error to be ±10%.

Activity [Bq]
Sample Mass [g] Expos. [h] Delay [h] 24Na 42K 46Sc 51Cr 59Fe 60Co 65Zn 82Br 122Sb 140La 198Au 233Pa 239Np
PPO 21-635 UA32-33 2.2143 1.0 84.0 3483±3 7.0±2.0 3.8±0.3 108±0.3 1.6±0.08 -0.083±0.076 -0.66±0.35
Empty vials UA32-33 5.2173 1.0 84.283 1570 -1.3±10 15.8±11.0 4.7±1.9 88±2.1 -0.4±1.8 -4.1±2.6 2.3±1.1 -4.0±2.9 2.3±1.1
Virgin vials UA 9-11 7.8803 5.0 60.0336 0.94±0.04 31±1 3.45±0.09 3.3±0.03 4.38±0.08



The table below lists the concentrations corresponding to the above activities and irradiation parameters. Data for batch 21-635 is compared to that derived for 21-634 in March 2001. The errors given below are the quadratic sum of the statistical and a 10% systematic error. The scaling of the neutron flux along the irradiation rabbit has not been taken into account here.


Concentration
Sample Na
[µg/g] 		K
[ng/g] 		Sc
[pg/g] 		Cr
[ng/g] 		Fe
[ng/g] 		Co
[ng/g] 		Zn
[ng/g] 		Br
[ng/g] 		La
[pg/g/] 		Au
[pg/g] 		Th
[pg/g] 		U
[pg/g]
PPO 21-635
UA32-33
acid extrct.		 3.1±0.3 106±32 5.7±0.8 21.4±2 9.6±1 <44 <43
PPO 21-634
UA19-21
acid extrct.		 1.8±0.2 302±104 14±1.4 6.2±0.6 176±18 1.5±0.2 70±7 7.1±0.7 21±3 4.6±0.5 6.1±2.2 -5.5±2.2
PPO 21-634
CIT
no extrct.		 1.2±0.2 19±15 <59 <0.65 950±700 <36 19±2 <20 <32 <450 <410
Large vials
UA Mar. 2001		 0.45±0.05 6.3±15 25±14 7.7±0.8 100±10 0.6±0.06 8.3±0.8 3.7±0.4 2.7±0.7
Large vials
CIT Jan. 2001		 1.1±0.1 31±15 12±2 310±40 0.65±0.08 21±2 3.2±0.3 81±9 30±23 <40
Large vials
CIT Mar. 2001		 0.37±0.05 18±0.3 <11 0.34±0.07 <160 10.5±4 1.2±0.1 7.0±0.9 95±11 <58 <33


The data presented here does not exhibit a large difference for any of the observed elements for PPO batches 21-634 and 21-635.
This page is maintained by A. Piepke
Last update July 17, 2001