ACTIVATION ANALYSIS OF TRACE OXYGEN AND NITROGEN IMPURITIES IN HIGH-PURITY MATERIAL

摘要

PURPOSE:To improve analysis sensitivity by converting an oxygen impurity to 13N and a nitrogen impurity to 11C by proton irradiation, separating nitrogen and carbon and making determination of the oxygen impurity and the nitrogen impurity. CONSTITUTION:A measuring sample is activated by projecting the proton thereon. The following nuclide forming reaction takes place: 16O+P 13N+alpha, 14N+P 11C+alpha. The activated sample is heated to 1,400 deg.C to oxidize the carbon and to gasify the nitrogen. The trace gas for analysis gasified in a heating furnace 1 is carried by a carrier gas and is introduced into a lime packed column 3 where C is absorbed and separated. The remaining gas passes a disoxidizing column 4 where the oxygen is removed and thereafter, the gas is carried to a molecular sieve 5 where the nitrogen is captured. The determination of the oxygen impurity and the nitrogen impurity is executed. The analysis sensitivity is thereby improved.