The efficiency of universal techniques of atomic emission spectrography and spark source mass spectrography for the analysis of non-conducting powders

Abstract

Two semi-quantitative universal techniques for the analysis of very different non-conducting powdered materials were compared with regard to matrix influences on the reliability of the analytical results. One of these techniques is based on atomic emission spectrography (AES) and was proposed by K roonen and V ader[4] several years ago. The other one is based on spark sources mass spectrograpny (SSMS) and has been developed in our laboratory more recently. To evaluate matrix effects objectively, a “total factor of variation”. V tot, was calculated as the antilogarithm of the standard deviation of the logarithms of analytical results over all matrices. The factor was compared by statistical analysis of variance to an analogous factor v rep, estimated in each case from a set of replicate determinations in one matrix and thus representing the precision of the technique. The results show that in the case of the SSMS technique v tot varies from 1.6 to 1.9 and only sometimes exceeds v rep slightly (probability P = 0.95). On the other hand for the AES procedure, v tot varies from 1.4 to 2.3 and always exceeds v rep, with a high significance ( P > 0.99). However, precision is higher in AES. From the results, the conclusion is drawn that SSMS is more suitable for elaboration of universal techniques, in the case of non-conducting powders just as in the case of compact metals.