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Abstract  

The Bouregreg river basin is located in the Moroccan Central Massif which consists mainly of Palaeozoic formations that were subject to the Hercynian orogeny. This study documents the background geochemistry and hydrochemistry of the Bouregreg river basin, focusing on the distribution of major and trace elements. Rock samples were collected at nine locations along the Bouregreg River and its tributaries in the winter of 2005. Major (Al, Fe, Mn, Na, K and Ti) and trace (Rb, Cs, Sr, Sc, Ba, Cr, V, Co, Ni, Zn, As, Sb, La, Ce, Nd, Sm, Tb, Dy, Yb, Lu, Hf, Ta, Mo, Th and U) elements were analysed using instrumental neutron activation analysis. Data show that most of the geochemistry and hydrochemistry are related to regional and local geology. The geochemical heritage of geological environment in the Bouregreg river basin is very important, that results from the more compatible behaviour and the inertia of some elements during the weathering (3d transition elements (Co, Ni, Cr,…), interne transition elements f (lanthanides, Zr, Hf, Nb, Ta,…)). The geochemical homogeneity of the basin shows also heritage during the crustal accretion (magmatism-metamorphism-sedimentation) and the typology of this continental area is the same that the upper continental crust. Some anomalously high heavy metal analyses, particularly for As and Sb, may be related to anthropogenic activities.

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Abstract  

There has been an increasing interest in the consequences of the effectof discharge of effluents containing chemical elements into the marine environment.Here, we present the determination of a number of heavy metals in sedimentsfrom the Ribble Estuary in the north-west of England. Sediment cores wereobtained from the Ribble estuary and the cores were subdivided into 5 cm segmentswhich were then freeze dried. Part of the material so obtained was then usedto produce samples with particles of a given size range, since uptake of heavymetals by sediments is very particle-size dependent. Selected samples werethen reactor irradiated for instrumental neutron activation analysis. Theaims of this present study are to establish depth and longitudinal distributionsof heavy metals at selected site locations and to investigate the criticalsediment parameters that influence the uptake and retention of such contaminants.

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Abstract  

This paper shows the result of soil-plant relation in samples from Cuban sugar canes of different soil types and cane varieties, using INAA from a thermal reactor. The behavior of minor and trace elements in sugar cane leaves is unifor and independent of sugar cane variety of type of soil. The soil-plant relation shows four principal groups of micro elements, according to their absorption by the plant.

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Abstract  

In Algeria, bread is the staple food, produced in different kinds from local and imported wheat. Most of it is not subjected to micro-elemental analysis. The objective of this study is to determine quantitatively the traces elements in samples wheat grains produced locally from different cultivated provinces in Algeria. Trace elements (Co, Cr, Cs, Fe, Rb, Sc, Se and Zr) were determined using neutron activation analysis. The results show that the contents of the traces elements in the studied samples were within the safety baseline of all the assayed elements recommended by WHO/FAO except for cobalt in El Harrach province. The analytical results showed that chromium was undetectable in all samples except for Constantine, Ain Mlila and Setif provinces. However zirconium content in a few samples exceeded the permissible level.

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Abstract  

Since there is no database in Libya defining the intake of the individuals from different essential (minor and trace) and toxic elements provided through food, drinking water and aerosol, a project has been proposed with the cooperation of IAEA to determine the concentration of a number of elements such as Cs, Fe, Cr, Rb, Sc, Se, Co, Zn in the three mentioned sources. Emphasis was placed on the use of nuclear and nuclear-related techniques. In this paper, the primary results are presented for the concentration of minor and trace elements in some vegetables, spices and other foods which are widely used in the Libyan meals. Instrumental neutron activation analysis utilizing a 10 MW water pool reactor and a γ-ray spectroscopy facility was employed. For quality control, certified reference materials were analyzed simultaneosly with the samples which show good agreements compared with the certified data. Emphasis was given to both elements iron and zinc for their importance.

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Abstract  

Brain samples obtained from the Netherlands Brain Bank were taken fromthe superior frontal gyrus, superior parietal gyrus and medial temporal gyrusof 'normal' and Alzheimer's disease subjects in order todetermine elemental concentrations and compare elemental composition. Brainsamples from the cortex were taken from 18 subjects, eight 'normals'(6 males and 2 females) and eleven with Alzheimer's disease, (1 maleand 10 females) and the following elemental concentrations, Na, K, Fe, Zn,Se, Br, Rb, Ag, Cs, Ba, and Eu were determined by instrumental neutron activationanalysis (INAA). The element which showed the greatest difference was Br,which was found to be significantly elevated in the cortex of Alzheimer'sdisease brains as compared to the 'normals' at significance (p<0.001).

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Abstract  

INAA and anti-Compton spectrometry has been employed in the analysis of test bone samples. Validity and accuracy of the method were checked by the use of two biological reference materials procured from the National Institute of Standards and Technology, USA (NIST) and the International Atomic Energy Agency, Austria (IAEA). NIST 1486 Bone Meal (ca. 200–800 mg) and A-11 Milk Powder (ca. 200–600 mg) samples were irradiated in the 100 kW TRIGA Mainz reactor. Concentrations of 13 elements in both biological reference materials have been determined and were found in good agreement with the certified and provisional values.

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Abstract  

Sensitive nondestructive instrumental neutron activation analysis (INAA) technique has been applied for the determination of rare earth elements (REEs) (Ce, Eu, La, Lu, Sm, Tb and Yb) in phosphate rocks (PR) and granulated single super-phosphate (GSSP) fertilizer samples from Hazara district of Pakistan. The comparison of the PR with product fertilizers shows that most of the quantified REEs were found to be in lower contents in the fertilizers. Six fertilizer samples with different N, P and K ratio for distinctive application to plants were also characterized. The REEs in these showed irregular patterns that can be attributed to difference in their manufacturing and chemical processes. The REEs contents of local phosphate fertilizer were found to be lower in comparison to the values cited in the literature; however Ce is relatively high. For quality assurance fair agreement was found between the results obtained for reference materials IAEA SL-1 (Lake Sediment) and GSJ-JR-1 (Rhyolite).

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Acta Alimentaria
Authors: N. Adányi, M. Váradi, I. Sziklai-László, P. Snyder, R. D. Snyder, and M. Á. Cser

Total daily Se intake was determined by duplicate diet collection, venous blood samples were taken and urine was collected over 24 h in order to measure selenium input and output in healthy, American and Hungarian children aged 8 to 17 living in Budapest. The American children consumed not only locally processed food. Food samples were weighed, mixed, homogenised and the Se content was determined by Instrumental neutron activation analysis (INAA). The Se concentration of blood, plasma and urine samples was determined by atomic absorption spectrometry-hydride generation (AAS-HG) after wet digestion.  Se intake calculated for wet weight was 62±18.5 mg/day in American children. In the Hungarian children the mean Se intake was about 35% less than in the Americans. Se concentrations in plasma were 0.84±0.16, in whole blood 1.13±0.17 mmol l-1 in the Americans, higher than those in healthy Hungarian children (0.64±0.10 and 0.83±0.12 mmol l-1, respectively) of similar age and gender. Urinary Se output calculated for creatinin was higher in the children from abroad (27.0±9.5 mg Se/day/g creatinin) compared to Hungarians (11.0±5.0 mg Se/day/g creatinin).

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Abstract  

Instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectroscopy methodology was developed to characterize the hazardous and other inorganic trace element constituents in new and used domestic plastic food containers. INAA due to its non destructive, highly sensitive, multielement and low detection limits characteristics was found to be a good technique for the characterization of polymeric products. Through the variation of irradiation, cooling and counting protocols Al, Ba, Br, Co, Cr, Eu, Fe, Hg, K, Mn, Na, Nd, Sb, Sc, Th, Ti, V and Zn were determined, while Atomic Absorption Spectroscopy was used as complementary technique to quantify toxic inorganic elements such as Cd, Pb and Cu. These elements are thought to originate from the polymer manufacturing processes. It was found that there was gradual increase in the concentration of most of these elements from new to used plastic samples. Moreover it was also observed that these inorganic elements are present in higher concentrations in the lower grade containers as compared to the high quality containers. It was also observed that the good quality containers even with the long usage do not degrade to such an extent as the low quality containers.

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