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Abstract  

Instrumental neutron activation analysis (INAA) has been employed in the investigation of mass balance for mercury species analysis in the analytical process. A new human hair reference material (IAEA-085) was analyzed for methylmercury using a solid/liquid extraction procedure, with samples of extracts, residues, and untreated samples being analyzed by INAA. The certified reference material NIES CRM No. 13, human hair, was analyzed in parallel. From the results obtained through the mass balance studies, it was found that the extraction procedure was quantitatively complete, and that there was no difference between the mass balance of Hg and the total Hg in the untreated materials.

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Abstract  

Instrumental neutron activation, proton induced X-ray emission and energy-dispersive X-ray fluorescence procedures were employed for trace element determinations in samples of fractionated air particulate matter deposited on filters. The techniques are well suited to analyse the generally small samples. However, indications of bias between techniques were found in the analysis of individual filters. This may be rectified with the development of matched reference materials. The three techniques were used in this work to determine trace elements in bulk samples of air particulate matter and in a set of intercomparison samples of fine air particulate matter on filters. The test results on these materials showed good agreement among the employed techniques and demonstrated the quality potential of air particulate analyses.

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Abstract  

Solutions of three useful atmospheric particle tracer materials, i.e., isotopically-enriched 196Hg, and organometallic complexes of 147Nd (T 1/2 = 11 d) and Ir, were dispersed into a pilot-scale coal combuster to determine partitioning between flue gas and suspended particle phases for Nd and Ir, and information on the chemical form of Hg tracer using nuclear analytical methods. Flue gas samples for 147Nd, and Ir analyses were collected using cascade impactors at reduced and near flue gas temperatures; 196Hg was sampled using an impinger method, and analyzed for 196Hg after activation on cystine paper and by atomic absorption for total Hg. Solvent extracts of the impactor samples were also analyzed to determine the integrity of the tracer complexes. The results indicate that interaction with the particles tends to degrade the complexes, that major fractions become associated with particles, and that 96% of the Hg tracer was collected as HgCl2, whereas, 85% of the natural Hg was collected as Hgo.

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Abstract  

The sensitivity and precision of instrumental neutron activation analysis (NAA), radiochemical neutron activation analysis (RNAA), and thermal ionization mass spectrometry (TIMS) are compared for the determination of Ir in ambient size-fractionated aerosol particulate samples. The results of the TIMS analyses indicated high analytical precision (0.2% at >50 pg Ir), but the sensitivity of detection was limited by blank values (300–500 fg). The sensitivities for INAA and RNAA were comparable, i.e., 60 to 90 fg in size-segregated particulate samples.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: R. Zeisler, S. B. Clark, S. J. Parry, G. R. Choppin, S. B. Clark, P. R. Danesi, S. J. Parry, M. Rossbach, C. Williamson, Zhifang Chai, R. Zeisler, S. J. Parry, and S. F. Heller- Zeisler

Summary  

Since the 1970's, concern about the training of radiochemists in the US has been increasing along with the age of nuclear work force, while the number of academic institutions offering undergraduate courses and the number of radiochemistry faculty has been steadily decreasing. To address this problem, a summer program has been offered through the American Chemical Society to undergraduates since 1984. Students compete nationally for this opportunity, and those selected receive a 3,000 stipend. In addition, all other expenses are paid. In this manuscript, the curriculum is described, along with the need for additional training programs and their impact.

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