ENTRY 23704 20200520 228823704 0 1 SUBENT 23704001 20200505 228823704 1 1 BIB 8 31 23704 1 2 TITLE Radiochemical investigation of 238U spontaneous fission23704 1 3 AUTHOR (M.N.Rao) 23704 1 4 REFERENCE (J,RCA,8,12,1967) 23704 1 5 INSTITUTE (2GERKLN) 23704 1 6 SAMPLE .Pitchblende from Eldorado Mines, Great Bear Lake, 23704 1 7 Canada, ~50% U(3)O(8) - for long-lived nuclides. 23704 1 8 300 g - for Sr. 23704 1 9 .Pure UO(2)(NO(3))2*6H(2)O . 23704 1 10 900 g for Cs, 2.3 kg for Ba. 23704 1 11 DETECTOR Phillips low-background assembly of pancake type 23704 1 12 G.M.Sonde 18516 Sample counter with a Fe-Cr window of 23704 1 13 10 mg/cm2 thickness. A stainless steel dome shaped 23704 1 14 anti-coincidence umbrella, filled with Ar and halogen 23704 1 15 quencher - as ring counter. 23704 1 16 Counting efficiency was determined by Sr-90, Y-90, 23704 1 17 P-32, Na-22 samples of various thickness with 23704 1 18 uncertainty 10-15 %. 23704 1 19 METHOD (CHSEP) 23704 1 20 Sr-89 Sr-90 Cs-136 Cs-136 Ba-139 23704 1 21 U-238,kg 0.173 0.173 0.763 0.371 1.12 23704 1 22 Chem.yield,% 50.4 50.4 30.3 28.2 45.1 23704 1 23 Counting efficiency,% 35.0 13.5 37.5 38.0 35.2 23704 1 24 +- +- +- +- +- 23704 1 25 1.0 0.3 1.0 1.0 0.9 23704 1 26 Activity at t=0,cpm 0.5 0.3 2.8 1.3 4.8 23704 1 27 +- +- +- +- +- 23704 1 28 0.2 0.1 0.5 0.3 0.8 23704 1 29 Equilibrium activity, 2.7 4.3 5.5 5.6 4.5 23704 1 30 dis/sec/gU x10**-4 +- +- +- +- +- 23704 1 31 0.9 1.4 1.1 1.2 1.0 23704 1 32 HISTORY (20200520C) M.M. 23704 1 33 ENDBIB 31 0 23704 1 34 NOCOMMON 0 0 23704 1 35 ENDSUBENT 34 0 23704 199999 SUBENT 23704002 20200520 228823704 2 1 BIB 5 26 23704 2 2 REACTION 1(92-U-238(0,F)MASS,CHN,FY) 23704 2 3 2(92-U-238(0,F)MASS,CHN,FY,,,DERIV) 23704 2 4 ANALYSIS 1. Yield was calculated as 23704 2 5 (NiLAMBLAi/(N238*LAMBLAsf))*100, where 23704 2 6 NiLAMBLAi - equilibrium activity of the fission product23704 2 7 with mass number i, 23704 2 8 N238 - number 0f U-238 atoms, 23704 2 9 LAMBDAsf - U-238 spontaneous fission decay constant, 23704 2 10 (7.8+-0.9)*10**17 1/yr. 23704 2 11 2nd run - (3.96+-0.4)*10**-4 dis/sec per g U-238. 23704 2 12 2. Smooth mass yield from these data and data of other 23704 2 13 experiments ( see 5 REL-REFs). 23704 2 14 REL-REF (R,13058001,H.R.Heydegger+,J,JIN,12,12,1959) 23704 2 15 (R,13223001,M.P.Menon+,J,JIN,26,401,1964) 23704 2 16 (R,,M.Attrep,T,ATTREP,1965) Univ.Arkanzas, PhD disser. 23704 2 17 Three refs. for data used for smooth mass yield. 23704 2 18 (R,13063001,M.N.Rao+,J,PR,147,884,1966) 23704 2 19 (R,14581001,G.W.Wetherill,J,PR,92,907,1953) 23704 2 20 (R,13483001,B.G.Young+,J,CJP,38,1,1960) 23704 2 21 (R,13472001,F.T.Ashizawa+,J,JIN,5,12,1957) 23704 2 22 (R,23559001,H.Menke+,J,RCA,6,76,1966) 23704 2 23 5 refs. for data used for smooth mass yield and for 23704 2 24 comparison in Table 2 23704 2 25 ADD-RES Independent fission yields calculated by Pappas' method23704 2 26 using smooth mass yields are on Fig.2 (table). 23704 2 27 STATUS (TABLE) Table 2 of Radiochimica Acta,v.8,p.12,1967 23704 2 28 ENDBIB 26 0 23704 2 29 NOCOMMON 0 0 23704 2 30 DATA 3 6 23704 2 31 MASS DATA 1DATA 2 23704 2 32 NO-DIM PC/FIS PC/FIS 23704 2 33 131. 0.6 0.4 23704 2 34 132. 2.32 2.0 23704 2 35 133. 4.21 3.2 23704 2 36 134. 4.94 4.2 23704 2 37 135. 5.39 5.1 23704 2 38 136. 5.93 5.8 23704 2 39 ENDDATA 8 0 23704 2 40 ENDSUBENT 39 0 23704 299999 ENDENTRY 2 0 2370499999999