Published online by Cambridge University Press: 18 July 2016
This date list mainly reports on samples processed from 1982 to 1991. Each sample is converted to methanol. Radiocarbon is measured in a Teflon™ vial containing a mixture of 40 g of methanol and 50 cc of xylene, 1% Butyl PBD and 0.1% PBBO using low-background scintillation counters Aloka LSC-800, LB-I and LB-III. The background of LB-III is ca. 8 cpm and counting efficiency is ca. 70%. The recent 14C standard used is 95% of NBS oxalic acid; 5568 yr is used as the half-life of 14C.