Page 45 - PR 2014 2016 07 Nuclear Science and Technology

Nuclear Science and Technology | Progress Report 187

Sciences, Gent, Belgium, has been increasingly
used, as it requires only a single comparator
197
such as Au for multielemental determination
instead of multielemental standards required
in the relative method.

The INAA relative method is considered one
of the most accurate analytical methods, but
more and more neutron activation laboratories
in Brazil and in other countries all over the
world are using the k -INAA method, due to
0
the quite accurate results obtained and the im-
provement of the analysis procedure and time.

The objective of this study was to compare the
results obtained by relative INAA and k -INAA
0
methods at the IEA-R1 reactor of IPEN. The
same input parameters (sample mass, nucle-
ar data, net peak area for the same gamma
line and the same measurement and same
cooling and measurement times) were em-
ployed in the analysis of reference materials
of different matrices: basalt BE-N (IWG-GIT),
SOIL-5 (IAEA), Buffalo River Sediment (NIST-
BRS-8704), INCT-MPH-2 Mixed Polish Herbs,
Oyster Tissue (NIST-SRM-1566b) and Bovine
Liver (NIST-SRM-1577c). The k -standardiza-
0
tion method has been applied by using the
k _IAEA software. To evaluate the accuracy of
0
the results, bias (%) and En-number test were
applied to the results obtained for more than
20 elements in the analysis of the reference
materials. The results pointed to the possibil-
ity of using the k -INAA method with good
0
accuracy. (Financial Support: CNEN, CNPq).