Mise au Point D'Un Dispositif D'Analyse Radiométrique de Haute Sensibilité, Pour Éluats Chromatographiques Gazeux

The setting up of a radioactivity measurement device of chromatographic gazeous eluates of minute volumes (maximum injection of 0,4λ) has been realized for weak β energy isotopes (C-14 and H-3). The radiochemical detection apparatus is an electrolytic copper ionization chamber. The measure of the current is made by means of a vibrating-reed electrometer. The electronic stability of the apparatus is satisfactory. The background due to α's is limited to 10-15 discontinuities an hour. The elution of high boiling point compounds is feasible by heating the ionization chamber and extension device which permits the thermic isolation of the detection chamber. The sensitivity of the whole reaches 1.000 dpm±500 with C-14 (C*H3OH) and 15.000 dpm with H-3 (C2H5CH*3).