Lead determination analysis

Lanthanum in solution, determination by absorption-edge method, 140 Lead, determination by x-ray emission spectrography, 328 see also Tetraethyllead Tetraethyllead fluid trace analysis by x-ray emission spectrography, 163, 225-227 Light elements, background in determination, 217-219... 

Values of the dipole moment ratio of PNS are obtained from dielectric measurements. From thermoelastic experiments, performed on polymer networks, the temperature coefficient of the unperturbed dimensions is determined. Analysis of these results using the RIS model is performed leading to the parameters given above. 

A lead blank (500 L of distilled water containing 25 /xg/L of Pb(N03)2) was pumped onto the ion-exchange columns only. The aqueous eluents were combined with the acetonitrile eluant for each column NaCl was added to separate the aqueous and organic phases. After separation, the aqueous phase was extracted twice with acetonitrile. The extracts from each column were pooled and reduced in Kuderna-Danish evaporators to a final acetonitrile volume of 4-6 mL and then diluted to a known volume with distilled water for atomic absorption spectroscopic (AAS) determination of lead. AAS analysis was on an IL 951 with an air-acetylene flame the 217.0-nm lead line was used. 

Leipziger, F. D., and W. J. Croft Geologic age determination by direct lead isotope analysis. Geochim. cosmochim. Acta 28, 268 (1964). 

On some of the samples, lead determinations were also made however, lead was near or below the detection limit value 0.5 nmol/kg). Consequently, this method is not suitable for the analysis of lead in... 

Mg(N03)2 6 H20 Suprapur, and (NH4EHPO4 Pro analysis, both from Merck, were used for matrix modifier preparation for lead determination by graphite furnace analysis. 

All measurements were performed with the program GIRAF and with the previous ones without shutdown of the instrument at the same analytical conditions (according to Perkin-Elmer cookbook ) by the same analyst with the same reference materials applied as calibration and test solutions. The matrix modifier for lead determination by graphite furnace analysis was used separately from the reference materials, i.e. was not mixed with them. The matrix modifier for sodium determination by flame atomic emission analysis was introduced in all corresponding solutions (the blank and the reference materials for the calibration and test). Three replicates of all measurements were made. 

Fig. 9 A set of TPD spectra of Au (mle= 197) on a 2.5-nm-thick Si02 thin film on Mo(l 10) at Au cluster coverages ranging from 0.2 to 5.0 ML. The inset shows a plot of E uh determined from leading edge analysis. (View this art in color at www.dekker.com.)...

Recently reported techniques for lead determinations also include polymerized crystalline colloidal array (IPCCA) for the detection of Pb in high ionic-strength environments, such as body fluids (Asher etal. 2002). Flow injection (FI) analysis may be used to measure lead in environmental solid samples with spectroscopic detectors (Yebra-Biurrun and Moreno-Cid Barinaga 2002). Other techniques include ultra-fast high-performance liquid chroma-... 

The food they bought is free of lead. The dishes they use at home are the source of the lead. Determine whether the dishes contain lead. Analysis of the pottery showed that lead was present in the glaze. 

The so-called Delves cup method was applied in many laboratories for PbB determination before the graphite furnace technique reached its highly developed present stage. The method was published by Delves (1970) and at that time it was one of the first reliable micro methods requiring only very small amounts of blood. It has been adopted by several authors for the analysis of capillary blood as well as for lead determinations on disks punched from filter paper previously spotted with a drop of blood (Cernik and Sayers, 1971 Cernik, 1974 Delves, 1977). 

In elemental analysis by ICP-MS, a difference in the isotopic composition between the sample and the calibration standard leads to a bias in the measurement result, that is, the elemental content determined. In serious routine analysis, the isotopic variation of certain elements therefore needs to be considered. For lead determination, often the ion currents of the isotopes ° Pb, Pb, and Pb are summed and this sum is used for the calculations, because the sum of all isotope amount fractions is one and therefore is not susceptible to isotopic variations. However, two approximations are included first, the ion current of Pb is not used owing to its low isotope amount fractions and the interference from... 

Renson, V., Coenaerts, J., Nys, K., Mattielli, N., Astrom, P., and Claeys, P. (2007) Provenance determination of pottery from Hala Sultan Tekke using lead isotopic analysis preliminary results, in Hala Sultan Tekke 12. Tomb 24, Stone Anchors, Faunal Remains and Pottery Provenance, Studies in Mediterranean Archaeology, Vol 45 (12) (eds. P. Astrom and K. Nys), Paul Astroms Forlag, Savedalen, pp. 53-60. 

M.S. Di Nezio, M.E. Palomeque, and B.S. Fernandez Band. A sensitive spectrophotometric method for lead determination by flow injection analysis with on-line preconcentration. Talanta 63 405-409, 2004. 

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