The main objective of this work was to study how the
k
0
-standardisation method of neutron activation analysis performs when applied to Moroccan medicinal plant samples. Irradiation was carried out ...at the Moroccan Triga Mark II research reactor at CNESTEN. Standard references material from NIST and WEPAL were used for internal quality control, mainly to ensure accuracy and precision measurement. More than twenty elements were determined in eight medicinal plants analysed. Mg, K, Ca, Cl, Na were observed as major in high concentrations while rare earth elements and toxic elements were found as traces elements. The results obtained in this study allowed these plants to be classified according to their composition of trace elements, macro-elements, rare earth elements and toxic elements.
This study investigates the concentrations and accumulation levels of rare earth elements (REEs) in soil samples collected from gold-mining sites in Sudan in order to study the distribution of REEs ...and discuss their concentrations around the gold mining areas in Sudan. The presence of REEs was determined through the neutron activation analysis technique. Irradiations have been carried out using the pneumatic tube system (PTS) and rotary specimen rack (RSR) facilities of the Moroccan TRIGA Mark II research reactor. Measurements were made using a well-calibrated HP-Ge detector for energy and efficiency, while SRM–NIST 2586 was used as a reference material to ensure the quality of the obtained results.
The aim of this work was the characterization of the neutron flux parameters in two irradiation facilities; pneumatic tube system (PTS) and rotary specimen rack (RSR); at the Moroccan Triga Marck II ...research reactor using
k
0
-IAEA and KayWin softwares. The analysis of several combinations of flux monitor sets is the basis for this study. The efficiency calibrations of the detector used have been carried out using the
k
0
-IAEA software and then exported to the KayWin software for the determination of the
f
(thermal to epithermal neutron flux ratio) and
α
(deviation from the 1/
E
distribution) parameters.
The National Center for Energy, Sciences and Nuclear Techniques (CNESTEN)'s Training Research and Isotope Production General Atomics (TRIGA) Mark II is a pool-type light water moderated and cooled ...research reactor operating at a maximum steady state thermal power of 2 MW. The reactor was designed to be used as a training facility for reactor operators, neutron activation analysis, isotopes production, and for implementing different reactor physics experiments. This article deals with the numerical and experimental characterization of reaction rates (RRs) in different irradiation channels inside the CNESTEN's TRIGA Mark II research reactor, located in Rabat/Morocco. The main objective of this study is to validate the calculated neutron RRs against the measured ones and to prove that the new TRIPOLI-4 model of the reactor is capable to reproduce the measured quantities. Therefore, the measurements were carried out using the neutron activation technique and gamma spectrometry measurements. Preliminary simulations were performed with TRIPOLI-4 transport Monte Carlo code to establish the experimental design and set up for activation foils experiments. The selected set of foils with known characteristics were irradiated, at different power levels, inside the irradiation facilities of the TRIGA reactor. The resulting activities were evaluated via <inline-formula> <tex-math notation="LaTeX">\gamma </tex-math></inline-formula> spectrometry measurements. Normalized calculated and measured RRs were compared, and a good agreement was shown for most nuclides, which indicates that the new detailed TRIPOLI-4 model of the TRIGA reactor can accurately predict the relative experimental RRs values. Further work is ongoing to analyze absolute RR values, as well as to carry measurements in other irradiation channels.
The main objective of the present study was to determine the concentration of major and minor elements contained in soil and phosphate rock samples collected in the prospective phosphate mining area ...in Hinda district. Samples have been analyzed using k0-neutron activation method through the Moroccan Triga Mark II research reactor. The results showed Al, Fe, K, Mg, Mn and Na as major elements and As, Br, Cr, V and U as minor elements, including rare earth elements in soils and phosphate rocks. These results were compared with other studies reported worldwide. Pollution indicators have been determined to assess pollution status.
Soils from a prospective phosphate mining area in the Hinda district of the Congo were analyzed using the ICP-MS technique in order to assess the environmental pollution and human health risks ...presented by potentially toxic elements (PTEs). The results showed that the mean concentrations of PTEs exceeded the global crustal average. Environmental pollution was assessed, showing the study area polluted by PTEs. Human health risk was also assessed, with the results showing the level of cancer risk greater for children than that for adults, indicating that children are more susceptible to the carcinogenic effects of PTEs than their adult counterparts.
Naturally occurring radionuclides and
137
Cs were measured in a sediment core and surface deposit collected from the bed channel of the Oualidia Lagoon located in the western Morocco. Major and rare ...earth elements (REE) profiles were determined by instrumental NAA technique.
210
Pb and
137
Cs were used to establish the sedimentation chronology over the last decades by using conventional models.
210
Pb displayed relatively higher concentrations and rate of supply to the sediment than typical levels found in other coastal areas in Morocco. REE ratios and Ce anomalies showed that the direct incorporation of particles from seawater to the bed sediment is the most important, followed by the terrigenous component.
The first installation around the tangential beam tube of the Moroccan TRIGA Mark II research reactor comprises combined instruments for Prompt Gamma Neutron Activation Analysis (PGAA) and Neutron ...Imaging (NI). The implementation of this project is divided over three main stages, namely the installation of the collimator and the primary beam shutter, which is a common section for introduction inside the reactor; the PGAA instruments’ installation; and finally, the installation of the PGNAA/NI combined instruments. The entire design was planned for this project, and detailed information about the first and the second stage is described in this work.
The purpose of this research is to develop a direct spectrometric approach to monitor soils and waters, at a lower cost than the widely used chromatographic techniques; a spectrometric approach that ...is effective, reliable, fast, easy to implement, and without any use of organic solvents whose utilization is subject to law limitation. It could be suitable at least as an alert method in case of massive contamination. Here, we present for the first time a catalog of excitation–emission and total synchronous fluorescence maps that may be considered as fingerprints of a series of homologated pesticides, in large use in Morocco, aiming at a direct detection of their remains in agricultural soils and neighboring waters. After a large survey among farmers, agricultural workers and product distributors in two important agricultural regions of Morocco (Doukkala-Abda and Sebou basin), 48 commercial pesticides, which are fluorescent, were chosen. A multi-component spectral database of these targeted commercial pesticides was elaborated. For each pesticide, dissolved in water at the lowest concentration giving a no-noise fluorescence spectrum, the total excitation-emission matrix (TEEM), the total synchronous fluorescence matrix (TSFM) in addition to synchronous fluorescence spectra (SFS) at those offsets giving the highest fluorescence intensity were recorded. To test this preliminary multi-component database, two real soil samples, collected at a wheat field and at a vine field in the region of Doukkala, were analyzed. Remains of the commercial Pirimor (Carbamate) and Atlantis (Sulfonylurea) were identified by comparison of the recorded TEEM, TSFM, and SFS to those of the preliminary catalog at one hand, and on the basis of the results of a field pre-survey. The developed approach seems satisfactory, and the fluorimetric fingerprint database is under extension to a higher number of fluorescent pesticides in common use among the Moroccan agricultural regions.
The Bouregreg river is one of the main rivers of Morocco, Its source being located in the Moroccan Central Massif and flows towards the Atlantic coast through the coastal Meseta. The Bouregreg river ...basin is located in the Moroccan Central Massif which consists mainly of Palaeozoic formations that were subject to the Hercynian orogeny. To evaluate the environmental status of the Bouregreg river water, sampling of the dissolved (<0.22 μm) and suspended (>0.22 μm) phases was performed at 10 sites along the Bouregreg river and its tributaries in the winter of 2005. Major (Na, Ca, K, Ti, Mn, Al and Fe), trace (As, Ba, Bi, Cd, Co, Cr, Cs, Cu, Hf, Li, Mo, Nb, Ni, Pb, Rb, Sb, Sc, Sn, Sr, Ta, Th, U, V, W, Y, Zn and Zr) elements and rare earth elements were analysed. The dissolved and particulate phase of the Bouregreg river draining these contrasting zones show similar characteristics to those observed in other major tropical rivers such as the Congo and Amazon, and vary in composition between the different source areas. Obtained data show that the spectra of the standardized concentrations for all the determined elements in the dissolved and the suspended phase have the same form whatever the station and that the whole of the elements is strongly deficient compared to the upper continental crust. The strong depletion in the suspended phase and the associated enrichment in the dissolved phase suggest that some elements such as Rb, Ba and Sr are the most mobile elements during the weathering processes. The removal of the most mobile elements from the bedrock concentrates all remaining elements in the weathered phases of the soils, from whence it can be removed mechanically. As and Sb are strongly enriched as well in the dissolved load as in the suspended load.
