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Abstract  

Instrumental neutron activation analysis (INAA) was applied to determine Ca, Cl, Mg, Mn, Na, Sr and Zn in dentine and enamel tissues from human permanent and deciduous teeth. Comparisons were made between the results obtained in these different dental tissues as well as those obtained in permanent and deciduous teeth. The findings obtained were also compared with the published data. The accuracy and the precision of the results were evaluated by analyzing certified reference material.

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Abstract  

Essential and non-essential elements in the parts (leaves, fruits) of several kinds of herbal tea and camomile marked in Italy were determined by polarised X rays fluorescence spectrometer (EDPXRF). The quality of data was assured by calibrating the instrument with certified reference materials. The elements are found to be present in different plants in various proportions depending to soil composition and the climate in which the plant grows.

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Summary  

Instrumental neutron activation analysis (INAA) was applied to determine the inorganic composition of leaves and extracts from three different species of Casearia genus plant (C. sylvestris, C. decandra and C. obliqua). Statistical analysis of the analytical data of leaf showed that the three Casearia species present similar elemental composition. Extract from C. sylvestris showed significantly different inorganic content in comparison with the two other species. Certified reference material NIST SRM-1515 Apple Leaves was analyzed for quality control.

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Abstract  

A very accurate and sensitive method for the simultaneous determination of trace amounts of Co and Ni in biological materials has been elaborated. The method is based on radiochemical neutron activation. Irradiation of samples in Cd-shielded channel of a nuclear reactor assures balanced activity ratio of58Co and60Co isotopes and favourable detection limits for both nickel and cobalt. Column chromatography (ion exchange and extraction) has been used for the quantitative and selective isolation of the determined radionuclides. High accuracy of the method has been demonstrated by the analysis of several certified reference materials.

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Abstract  

A relatively simple and rapid radioanalytical method, limited to milk, is adapted for investigating soil, biological and water samples for90Sr. The method is based on a selective separation and successive counting of equilibrium quantities of its daughter 90Y, which can be extracted by tributyl phosphate from nitrate medium and stripped by conc. ammonia solution. 90Y is separated from possible iron and measured by Cerenkov counting. The procedure is thoroughly tested with certified reference materials and used lately for determining90Sr in some environmental samples in the Riyadh region. The results obtained are given and discussed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: O. Rizo, E. Herrera Peraza, M. Manso Guevara, I. Pellón, M. López Reyes, M. Cabrera, and M. Montero Cabrera

Abstract  

The main results obtained during the characterization of the Triga Mark III reactor at NNRI, Salazar, Mexico, the development of the nonconventional multimonitor HAV-1, the use of Certified Reference Material (CRM) as multimonitor fork 0-factors experimental determination, and to study the reactor power and slowing-down thickness dependencies of the reactor flux parameters and its influence ink 0-INAA are presented. The experience of thek 0-INAA group at ISCTN, in the application of this analytical technique for different purposes is resumed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: P. Lam Ramos, D. Frías Fonseca, M. González Garcia, D. Aguiar Lambert, J. Estévez Alvarez, I. Pupo González, and D. López Sánchez

Abstract  

The objective of the present study was the elaboration of a procedure for the determination of Y, La, Ce, Pr and Nd in soils by spectrophotometry with Arsenazo III preceded by a separation-concentration stage, which includes coprecipitation and ion exchange. Multielement analysis by energy dispersive X-ray fluorescence (including Y, La, Ce and Nd) and flame atomic absorption spectrophotometry was carried out simultaneously in order to obtain a general characterization of the soil samples. Certified reference materials and statistical intercomparison of the obtained results were used to evaluate the accuracy of the methods. The precision was examined by analyzing replicate samples.

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Abstract  

The Ir, Au and Pd concentrations in three certified reference materials SARM-7, FC-1 and DZ-1 were determined by neutron activation analysis using -amino pyridine preconcentration. Good agreement between the reference values and our results was obtained, and the reliability of our method was confirmed. This method is suitable for ppb or sub-ppb levels of Ir and Au analyses in environmental and geological samples. The Ir and Au levels in a Chinese coastal sediment GBW07314 were also analyzed.

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Abstract  

Levels of essential and toxic trace elements in six marine species greatly in demand in the international market (canned pink clams, razor clams, clams, king crab, sardines, and frozen albacore tuna fish) were studied. A special laboratory adequately equipped for handling and preparing biological materials, is described. The elements As, Br, Na, Se, Hg, Cr, Fe, Zn and Rb were determined by INAA, while copper and cadmium content were determined using RNAA. Significant differences were found on comparing the contents of some toxic elements in mollusk and other samples of marine food. Various certified reference materials (CRMs) of the IAEA, NIST and NIES were analyzed for quality assurance purposes.

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Abstract  

Concentration levels of eight trace elements in 120 samples of human blood serum were investigated by Instrumental Neutron Activation Analysis (INAA) for the purpose of medical research. The elements Co, Cr, Cs, Fe, Rb, Sc, Se, and Zn were simultaneously determined by the relative method in comparison with inorganic standards treated under identical conditions. The process of analysis and its reliability was checked using human serum and IAEA certified reference material. Statistical results are expressed in ppm or ppb. Both normal and, if necessary, log-normal frequency distributions of all elements determined are presented, types of distribution curves are verified statistically on 95% level of probability.

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