Implementation of k
0
-standardization method of the INAA
at ETRR-2 research reactor
Mohamed Soliman
•
Nader M. A. Mohamed
•
M. A. Gaheen
•
E. A. Saad
•
S. K. Yousef
•
M. A. Sohsah
Received: 3 August 2010 / Published online: 15 October 2010
Ó Akade
´
miai Kiado
´
, Budapest, Hungary 2010
Abstract The k
0
-method of INAA standardization has
been implemented using the irradiation facilities of the fast
pneumatic rabbit and some selected manually loaded irra-
diation positions, which designated for short and long irra-
diation, respectively, at Egypt second research reactor. The
neutron flux parameters (f and a) in each site have been
determined using Zr–Au sets as neutron flux monitors. The
reference materials coal NIST 1632c and IAEA-Soil 7 were
analyzed for data validation and good agreement between the
experimental values and the certified values was obtained.
Keywords Instrumental neutron activation analysis Á
k
0
-method Á Neutron flux parameters Á Au–Zr neutron flux
monitor
Introduction
Instrumental neutron activation analysis (INAA) is one of
the most important applications of Egypt Second Research
Reactor (ETRR-2). Since the first operation of ETRR-2 in
1998, only relative method is applicable for INAA stan-
dardization. This method of standardization has been
responsible for all of the analytical demand for the neutron
activation technique, meeting needs from external and
internal customers. In the relative standardization, the
unknown sample is irradiated together with a standard or a
reference material containing a known amount of the ele-
ment of interest. The standard or reference material is
measured under the same conditions as the sample. This
standardization method is still being regarded as one of
methods, which has the highest accuracy of INAA. How-
ever, it is not suited for multi-element analysis with regard
to the experimental workload and the impossibility to
quantify unexpected elements.
In the search for a solution to overcome the above-
mentioned disadvantages, attention has been directed
towards implementation and using of k
0
-INAA standardi-
zation. Moreover, the k
0
-method enhances the accuracy of
the analytical results by avoiding the unnecessary accu-
mulation of uncertainties on the underlying reference
materials used in the relative method.
k
0
-INAA standardization, which was originally pro-
posed by Simonits et al. [1], involves the simultaneous co-
irradiation of the sample and a comparator nuclide such as
197
Au. Accurate knowledge of the neutron flax parameters
in the irradiation sites, k
0
-factors, the detection efficiencies
and the specific activities of the nuclides in the sample, and
the monitor are needed for determination of the concen-
tration levels in the sample.
The objective of the present work was to assess the
applicability of the k
0
-INAA method using the experi-
mental system and irradiation protocol in the selected
irradiation positions of the ETRR-2 research reactor. For
this purpose, careful and complete characterization of the
neutron flux parameters in the selected irradiation positions
is needed in order to optimize their utilization for k
0
-INAA
standardization methods.
M. Soliman (&) Á N. M. A. Mohamed Á M. A. Gaheen
Egypt Second Research Reactor, Atomic Energy Authority,
Cairo, Egypt
e-mail: soliman.ma@gmail.com
E. A. Saad
Chemistry Department, Faculty of Science,
Ain Shams University, Cairo, Egypt
S. K. Yousef Á M. A. Sohsah
Radiation Protection Department, Nuclear Research Center,
Atomic Energy Authority, Cairo, Egypt
123
J Radioanal Nucl Chem (2011) 287:629–634
DOI 10.1007/s10967-010-0860-6