Abstract:
This study describes the technique and procedures used for the simultaneous determination
of elements involved in Instrumental Neutron Activation Analysis, applied
to some geological samples as a sensitive and non-destructive tool. Using Isotopic
Neutron Source, the delayed gamma-rays emitted due to neutron capture have been
applied for the investigation of the elemental constituents and concentrations of major,
minor and trace elements in such samples.
The experimental investigations were carried out at the scale of researcher's practices
at the chosen site by measuring soil/rock nutrient contents from hydrologically
isolated farmland/site plots. Using detailed sampling procedures with special precautions,
against contaminations, to yield meaningful results, soil/rock samples have
been collected from selected areas of East Gojjam, pulverized, homogenized and prepared
for irradiation.
The samples were properly prepared together with known standards of potassium iodide
or cupric sulphate or arsenic trioxide (one /or both at a time), and simultaneously
irradiated in to isotopic neutron
ux in the same irradiation position. After activation,
the samples were subjected to gamma-ray spectrometry, using a high-purity germanium
detection system and computerized multichannel analyzer. The gamma-ray
spectra from the irradiated samples were measured by high resolution gamma-ray
spectrometry with a calibrated germanium detector. Both qualitative and quantitative
approach to data collection and analysis were used in order to gain insight into what should be acceptable to the community.
The results obtained have a practical interest in view of possible applications to the
technology of extraction and exploration of a variety of industrial, metallic, cement
minerals, and geothermal energy and coal deposits. These results tend to agree with
the lowest values reported in the literature, and the analytical precision is su cient
for the determination of the standard deviation of the distribution of all elements in
East Gojjam and these results were brie
y discussed within the text of this research
work.
In carrying out the analysis, the best and most convenient method being the Instrumental
and /non-destructive Neutron Activation Analysis was adopted, and NAA
has matured and attained analytical competence providing not only rapid, quantitative,
qualitative, simultaneous, multielement analysis but also crucial validation
support to programmes using di erent analytical techniques. This method of analysis
is generally multi-element and experimental conditions can be designed to be
nondestructive to the sample, and it plays a leading role among analytical techniques
in the eld of environmental research related to human, animal and plant
health.
Studies of di erent radionuclide and trace elements in the environmental samples are
very important for health physics, research and education. Many forms of elements
are possible in environmental samples which may be hazardous for human being, animals
and also plants. Most of them have the potential for both benefcial and harmful
effects