Search results for "Lead Radioisotopes"
showing 5 items of 5 documents
A low-level spectrometer with a planar low-energy HPGe: shielding arrangement tests and system performance for 210Pb determination in air filter samp…
2001
A system for low-energy photon spectrometry using a planar germanium detector with appropriate specifications is presented. A spectrometric background investigation has been carried out with various detector shielding arrangements. The characteristics of the system for measurements of 210Pb in air-particulate matter on filters have been determined.
Apparent discrepancy in contamination history of a sub-tropical estuary evaluated through 210Pb profile and chronostratigraphical markers.
2005
Abstract Zn and Cd concentrations, stable lead isotopes and 210 Pb-derived chronology were determined in a sediment core sampled at Sepetiba Bay (South-eastern Brazil). During the last decades, the bay’s watershed has been modified by the increase of industrial activities and human interventions. In particular, Zn and Cd ore treatment plants were built near the coast in 1960 and 1970, respectively, and water has been diverted from the adjacent Paraiba do Sul River watershed since 1950. The core collected at shallow depth near the industrial area exhibits four successive events: (i) at 50 cm depth, a change in the 206 Pb/ 207 Pb ratio from about 1.162 to more than 1.18 might be the result of…
Possible impacts of Hg and PAH contamination on benthic foraminiferal assemblages: An example from the Sicilian coast, central Mediterranean
2007
The Palermo and Augusta urban/industrial areas (Sicily) are examples of contaminated coastal environments with a relatively high influx of unregulated industrial and domestic effluents. Three sediment box-cores were collected offshore of these urban/industrial areas in water depths of 60-150 m during two cruises (summers 2003/2004), dated by (210)Pb and (137)Cs, and analysed for total mercury concentration and total polycyclic aromatic hydrocarbon (PAH) concentration. Benthic foraminiferal assemblages were also examined (in terms of their distribution and morphology) to assess the potential use of benthic foraminifera as bioindicators of pollutant input and environmental change in these Med…
Mobility determination of lead isotopes in glass for retrospective radon measurements
2008
In retrospective radon measurements, the 22-y half life of (210)Pb is used as an advantage. (210)Pb is often considered to be relatively immobile in glass after alpha recoil implanted by (222)Rn progenies. The diffusion of (210)Pb could, however, lead to uncertain wrong retrospective radon exposure estimations if (210)Pb is mobile and can escape from glass, or lost as a result of cleaning-induced surface modification. This diffusion was studied by a radiotracer technique, where (209)Pb was used as a tracer in a glass matrix for which the elemental composition is known. Using the ion guide isotope separator on-line technique, the (209)Pb atoms were implanted into the glass with an energy of …
Determination of 210Pb concentration in the air at ground-level by gamma-ray spectrometry
1999
Abstract 210 Pb activity concentrations in the air of Palermo were determined by γ-ray spectrometric analysis of 323 particulate samples collected in the period September 1995–December 1996. For each sample, the air filtered through a cellulose filter paper was 8600 m 3 on average. The values of the daily activity concentration of 210 Pb were ranging from 136 to 3390 μBq/m 3 .