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Abstract  

Seventy-two leaf samples belonging to two cultivars of Cajanus cajanMillsp were analysed by instrumental neutron activation analysis (INAA). Thesamples came from plants treated with two doses of fertilizer containing eachof the following elements: B, Co, Cu, Fe, Mn, Mo, V and Zn, which were applied,individually, to the soil. The leaf samples were yielded at two differenttimes. The purpose of this paper is to elucidate the influence of each fertilizer,the dose and leaf harvest time, on the concentrations of Ca, Cu, K, Mg, Mn,Na and V, and the behavior of both cultivars in relation to the concentrationsof these elements.

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Abstract  

In this work instrumental neutron activation analysis was applied todetermine trace elements in nail clippings and to make a comparison betweenthe results obtained from samples from healthy children and those with cysticfibrosis (CF) disease. The findings indicated that fingernails from the CFgroup present higher concentrations of Cl, Cr, K and Na than those found inthe control group. On the other hand, the lowest concentrations for Cr werefound in the CF group. For the Al, As, Co, Fe, Mg, Mn, Se and Zn elementsthere were no differences between the results obtained for the CF and controlgroups. The quality control of the results was evaluated by analysing NIST1577b Bovine Liver and NIST 1566a Oyster Tissue standard reference materials.

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Abstract  

Instrumental neutron activation analysis (INAA) was applied to evaluatethe clinical status of equines, belonging to the Military Police of SoPaulo State, by means of Cu, Fe, Mn and Zn determinations in their hair. Comparisonof the results obtained in these analyses with reference values indicatedZn deficiency in the equines, Fe is in the minimum limit and the elementsCu and Mn are within the normal range.

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Solvent extraction studies using tetracycline as a complexing agent

XV. Separation of interferences in neutron activation analysis of lanthanides in rocks

Journal of Radioanalytical and Nuclear Chemistry
Author:
M. Saiki

Abstract  

A chemical procedure has been developed for the separation of U, Th, Fe, Sc, Na, Ta and Mo, which interfere in neutron activation analysis of the lanthanide elements in rocks. This methods in based on the extraction of interferents, before irradiation of the samples, using a solution of tetracycline in benzyl alcohol. The lanthanide elements remain in the aqueous phase and are coprecipitated with calcium oxlate or ferric hydroxide for irradiation and subsequent determination by gamma-ray spectrometry. Conditions for the separation of these interferences are examined determining the extraction curves. The chemical separation procedure was applied in the analysis of lanthanides in geological materials and the results showing the accuracy and the reproducibility of the method are presented. The sensitivity for all the lanthanides was determined.

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Abstract  

Instrumental neutron activation analysis (INAA) was applied to determine Ba, Br, Ca, Cl, Fe, K, Mg, Mn, Na, P, Sr and Zn in bovine and porcine rib bones. Precise results were obtained in analyses of freeze-dried cortical and trabecular bones separately, and also of whole bone ashes. Cortical tissues presented higher concentrations of Ba, Ca, Mg, Mn, Na, P, Sr and Zn than those obtained in trabecular ones. Comparisons were also made between the results obtained for bovine and porcine rib bones.

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Abstract  

The environmental changes that occurred in different periods can be identified through the increase or decrease of the concentrations of metals and other substances throughout sediment cores. The purpose of this study was to determine Al, As, Ba, Br, Cs, Eu, K, La, Mn, Sb, Sc, Sm, Th, Ti, U and V in a sediment core collected from São Paulo State South Seashore. Instrumental neutron activation analysis followed by gamma-ray spectrometry was the analytical method used. Results showed an abrupt decrease in the concentration of all elements in the 132–134 cm layer depth. This finding indicates an impact of anthropic activity.

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Abstract  

Instrumental neutron activation analysis (INAA) was applied to assess trace element concentrations in six samples of aspirin tablets acquired in São Paulo city, Brazil. Concentrations of the elements Br, Ca, Co, Cr, Fe, K, La, Na, Sc and Zn were determined. Comparisons were made between the results obtained with published data for aspirins from foreign countries. Certified reference materials, INCT-MPH-2 Mixed Polish Herbs were analyzed for quality control of the analytical results.

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Abstract  

In the present study, a radiometric method was applied for element migration determination from food plastic packaging to simulating solutions and foodstuffs. This method consisted of irradiating plastics with neutrons, its exposure for migration and radioactivity measurements in the food or food-simulating solutions. The migration was studied for water, juice, soft drinks, acidic fatty food and dairy product plastic packages. The results indicated Co, Cr and Sb migration to the simulating solutions and food. However, the contamination of these elements in food from packaging material was lower than the maximum limit values established by the Brazilian Surveillance Agency (ANVISA) legislation.

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Abstract  

Instrumental neutron activation analysis (INAA) was applied to assess element concentrations in eleven samples of mineral supplements/multivitamins acquired in drugstores and pharmacies in São Paulo city, SP, Brazil. Concentrations of Ca, Co, Cr, Cu, Fe, K, Na, Se and Zn were determined. A comparison was made between the results obtained with the labels of the mineral supplents. Certified reference materials, NIST SRM1400 Bone Ash and NIST SRM 1633b Coal Fly Ash were analyzed for quality control of the analytical results.

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Abstract  

Stability constants for the lanthanide elements complexes with tetracycline were determined by the methods of average number of ligands, the two parameters and by weighted least squares. The technique of solvent extraction was applied to obtain the values of the parameters required for the determination of the constants.

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