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Platinum Screen Collections
This is a Naval Research Laboratory experimental eollector. An
uncharged platinum screen is mounted vertically and held normal to
surface winds by a large vane, Two week total activity collegtions
made by NRL with this collector range up to that for 0.5 x 10°
cubic
feet of air, For individual twenty-four hour periods, total activities as high as 20 times that for gummed paper collectors have
been observed,
1.
Sample
Total Sr90 tn dpm
CL 536-P: 1.0 sq. ft., 80 mesh platinum screen,
Washington, D.C., collected 1600, February 1h,
26.0 + 1.7
1955 to 1600, February 21, 1955.
2. CL 537-P:
1,0 sq. ft., 80 mesh platinum screen,
1.9 + 0,8
Washington, D. Cs, collected 1600, February 21,
1955 to 1600, February 28, 1955.
3. CL 538-P: 1.0 sq/ ft., 80 msh platinum screen,
37.2 + 1.6
Washington, D.C., collected 1600, February 28,
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1955 to 1600, March 7, 1955.
DOE ARCHIVES
(70