A method for the preconcentration of Cu(II) by cloud point extraction (CPE) followed by its determination using neutron activation
analysis (NAA) was developed. The method involves the use of a nonionic surfactant, namely PONPE-7.5, and a chelating agent
1-(2-pyridylazo)-2-naphthol (PAN). The phase diagram of the surfactant was constructed and the effects of different additives
on the cloud point were investigated. Factors, such as the solution pH, ionic strength, temperature, and concentrations of
chelating agent and surfactant, which can influence the extraction efficiency of the metal, were optimized. The copper(II)
chelate was extracted into a surfactant-rich phase of small volume with a recovery of nearly 100% and a preconcentration factor
of 60. The small volume of the surfactant-rich phase obtained complies with the green chemistry concept, allowing the design
of extraction procedures having lower toxicity than those using organic solvents. The method was applied to tap water samples.
Authors:P. Robouch, G. Arana, M. Eguskiza, S. Pommé, and N. Etxebarria
The concepts of the Guide to the expression of Uncertainties in Measurements for chemical measurements (GUM) and the recommendations of the Eurachem document "Quantifying Uncertainty in Analytical Methods" are applied to set up the uncertainty budget for k0-NAA. The "universally applicable spreadsheet technique", described by Kragten, is applied to the k0-NAA basic equations for the computation of uncertainties. The variance components — individual standard uncertainties — highlight the contribution and the importance of the different parameters to be taken into account.
An instrumental procedure of activation analysis has been developed to study the distribution of some minor components in synthetic granates, ferrites and glass charges in some environmental materials. The determination of the degree of non-uniformity by NAA has been used for the preparation of uniform mixtures and for representative sample estimation in the analysis of nonhomogeneous materials.
Results for Se in several biological standard reference materials obtained by INAA and selective RNAA procedures developed in our laboratory, are presented and discussed. The comparison of selenium levels in selected blood plasma samples determined by non-destructive NAA and HG-AAS is also presented. The reproducibility and accuracy of the analytical procedure was tested and the results of these investigations were compared with the certified values.
A program for qualitative and quantitative analysis of spectra obtained by comparative NAA method is described. It includes peak search, calculation of essential peak parameters, isotope identification and estimation of concentrations and/or detection limits of nuclides, corrected for cooling time and decay during measurement. Corrections for blank samples and peak interference are performed as well. Uncertainties estimation of final results are performed according to the error propagation law. The program is aimed to help an experienced user to calculate the results of analysis but the possibility for automatic mode for routine analysis is provided as well.
Authors:A. Senhou, A. Chouak, R. Cherkaoui, M. Lferde, A. Elyahyaoui, T. El Khoukhi, M. Bounakhla, K. Embarche, X. Bertho, A. Gaudry, S. Ayrault, and D. Piccot
In this paper the performances and the limitations of three multi-elementary analysis techniques are compared applied to a study of air pollution biomonitoring in Morocco. These techniques are: (1) 14 MeV neutron activation analysis (14 MeV-NAA), (2) thermal neutron activation analysis using the k0 quasi-absolute method (k0-NAA) and (3) energy dispersive X-ray fluorescence analysis (ED-XRF). The experimental procedures and the control of the analytical results using certified reference materials are described and discussed. The three methods were confronted for the analysis of lichens, mosses and tree-barks. The complementarity of these methods enabled us to determine 43 elements in different samples. The most suitable method for each element was selected according to the sensitivity and selectivity necessitating the minimum corrections of the matrix effects and/or the interfering reactions.
Authors:M. Glascock, H. Neff, K. Stryker, and T. Johnson
An abbreviated NAA procedure has been developed to fingerprint obsidian artifacts in the Mesoamerican region. Despite the large number of available sources, an NAA procedure, which relies on producing short-lived isotopes, has been applied with a success rate greater than 90 percent. The abbreviated NAA procedure is rapid and cost competitive with the XRF technique more often applied in obsidian sourcing. Results from the analysis of over 1,200 obsidian artifacts from throughout Mesoamerica are presented.
Authors:S. Husaini, J. Zaidi, Matiullah, and M. Akram
Due to the significance of industrial waste water pollution, which creates severe health hazards in humans, this study concentrates
over the reduction and determination of the amounts of toxic metals/pollution parameters in the effluents leached from different
processes of the textile industry. The concentrations of metal ions were measured by using neutron activation analysis (NAA)
technique. The values of toxic metals such as As (49.1 ± 1.8 mg/L), Cu (42.7 ± 1.5 mg/L), Ni (41.1 ± 3.3 mg/L), Mn (51.1 ± 0.7 mg/L),
Sb (1.89 ± 0.04 mg/L), Se (0.41 ± 0.01 mg/L), Co (7.5 ± 0.3 mg/L), Cr (8.5 ± 0.5 mg/L) and Cd (1.21 ± 0.08 mg/L) were found
very high in crude textile’s effluents as compared to their standard recommended limits. The immense variation observed among
the injurious pollutants of the effluents i.e. pH, temperature, electrical conductivity, turbidity, biological oxygen demands,
chemical oxygen demands, total suspended solids, total dissolved solids, total solids etc. The toxic metals and injurious
pollutants in the unprocessed effluents have been reduced in the post filtration effluents up to 98% and 96% respectively
with the help of an ultra-filtration membrane therapy unit.
The early rapid growth, the attainment of maturity, current problems, and future prospects of NAA (neutron activation analysis) are discussed, each in reasonable detail. In particular, the nature and causes of its current problems are examined, and suggestions are presented for the solution of these problems. The author believes that vigorous action in suggested areas of concentration can reinvigorate the status of NAA as an important method of elemental analysis.
In the study of aluminum toxicity for plant, it is important to analyzethe behavior of Al in cells. We present how Al is taken up by tobacco cellsthrough lumogallion staining method developed by our laboratory. The fluorescenceintensity from the cell was increased rapidly between 4 and 8 hours of 1 mMAl treatment. To calibrate the fluorescence intensity from Al-lumogallioncomplex, Al amount in the cell was determined by NAA. When the same samplewas analyzed by ICP-AES, Al amounts in all the samples were 13% lower thanthose measured by NAA.