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Abstract  

IAEA and NBS biological certified reference materials have been analyzed by instrumental neutron activation analysis and concentration of 17 elements was determined. The elements determined were either completely missing or their certified values were not given in the original compilations. For quality assurance of our work, a comparison of data on missing trace elements in some of the CRMs has been presented. It seems that second round of analysis for the certification of these elements would be useful.

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Abstract  

Use of an enriched isotope as an activable tracer is proposed for the preconcentration of trace elements in neutron activation analysis. As a test of this method, contents of cadmium in various biological standard samples were determined by addition of an enriched116Cd tracer in the preconcentration step followed by neutron irradiation and -ray spectrometry. The principle, advantage, and limitations of the method are also discussed.

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Abstract  

Quantitative data on trace elements in two tobacco leaf (candidate) reference materials OTL-1 and VTL-2 prepared by the Polish Academy of Sciences and the Institute of Nuclear Chemistry and Technology, Warsaw, Poland, are presented and compard to recommended values, where available. By instrumental neutron activation analysis (INAA), as well as by radiochemical technique (RNAA) 30 elements were quantitatively determined and fair agreement was found between the results and recommended values for the first material.

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): Determination of trace elements in pumpkin seed oils and pumpkin seeds by ICP-AES. J. Anal. Atom. Spect. , 18 , 54–58. Steffan I. Determination of trace elements in pumpkin seed oils

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Abstract  

Neutron activation analysis has been used to assay the trace elements Co, Fe, Sc, Rb and Zn in pollen and derived sporopollenins. The method is capable of high precision and avoids the necessity for sample ashing and the introduction of reagent contamination. Rubidium was completely removed during the chemical isolation of sporopollenins and the remaining elements which survived chemical treatment were found in reduced amounts. The ratio of Sc: Fe in pollen and in several derived sporopollenins was found to be approximately constant. Results are discussed with reference to the possibilities of anomalous chemical behaviour of the elements resulting from irradiation.

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Abstract  

Instrumental neutron activation analysis has been applied for the determination of trace elements in five epiphytic lichens: Canoparmelia texana, Canoparmelia caroliniana, Parmotrema tinctorum, Parmotrema sancti-angeli and Usmea sp. that were collected at the same sampling area of the Botanic Institute, São Paulo, Brazil. The elemental concentration results showed that these five lichens can be chosen in the species intercalibration for biomonitoring studies. Also, some aspects related to the occurrence, tolerance to pollution, treatment and ease of sampling of the species are presented.

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Abstract  

The behavior of Zn and other trace elements in mice fed with Zn-deficient diet during the growing period (Zn-dcf. mice) was investigated. A correlation between Zn concentration and Co concentration was found in the liver of Zn-def. mice. Two types of correlation between Zn and Mn concentrations were also recognised for the same livers. These facts suggest that Zn and Co, and also Mn are antagonistic, and that Co- and Mn-substitution for Zn-proteins and other Zn-bound compounds may occur, and/or the substituted compounds may be synthesized in the liver of Zn-def. mice.

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Abstract  

Concentrations of eighteen trace elements at the sediment-water interface in Biwa Lake were determined by neutron activation analysis. Release of iron, manganese and arsenic from the sediment to the pore water was observed under anoxic conditions. The concentrations of Sb in the pore water as well as Na were nearly constant between the surface and the depth of 40 cm. The behavior of Sb differed from that of As at the sediment-water interface, since the partition coefficient of Sb differed from that of As.

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Abstract  

Similar distributions for 238U, 232Th, 226Ra, 210Po, 238,239,240Pu, 137Cs and trace elements were obtained in sediment samples collected along the Romanian sector of the Danube River and the Black Sea coast during 1994. The radionuclide and trace element accumulation in the investigated samples is discussed with respect to their geochemical behavior and the mineralogical structure of the samples. The latter, investigated by X-ray diffraction and cation exchange capacity of the same samples, proves to be an important factor in the selection of sampling sites for monitoring the pollution of river basins and the sea.

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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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