Scintillation counter for simultaneous assay of H3 and C14 in gas-liquid chromatographic vapors*

Abstract

An instrument for the assay of H3 and of C14 in gas-liquid chromatographic effluents is described. The radioactive analysis is practically simultaneous with the mass-analysis. By the use of coincidence circuitry and pulse-height analysis with discriminators it is possible to measure simultaneously two radioactive isotopes contained in the same sample. Furthermore the addition of a subtracting circuit to the electronic system (described in an Appendix) permits the independent recording of C14 and of H3 counts.