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The present work reports the results of a first study of elemental composition in airborne particulate matter (fine and coarse) collected at the Municipality of Centro Habana, Havana City, Cuba, using the PIXE technique. At present, there is not any information available about element contents in airborne particulate matter from this region. A five months sampling campaign was carried out, collecting the samples under an air flux of 20 l/min with a Gent SFU Sampler equipped with a system which allows the aerosol collection in both size fractions simultaneously. A total of 144 aerosol samples were collected. For the PIXE analysis, the samples were irradiated by 2.0 MeV energy protons from a 2MV Tandetron Accelerator. A total of 14 elements (S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb) were consistently detected with minimum detection limits from 1 ng/m³ to 10 ng/m³ for most of the elements. Enrichment factors were also calculated for both fractions in order to identify the natural and anthropogenic group of elements. The quantitative results obtained have revealed important information that has been used in a first attempt to understand and to characterize the atmospheric pollution of this area.

In this work, we present a review of the research developed by the PIXE Group of Ion Implantation Laboratory (Porto Alegre, Brazil) for the elemental characterization of food and beverages in general. Samples of coffee, wine, wine stoppers, mate tea leaves (Ilex paraguariensis) and tuna fish were analyzed using Particle-Induced X-ray Emission (PIXE) in order to determine their elemental compositions. Elements ranging from atomic number 11 to 82 were detected, and it was possible to observe differences in the elemental composition among different brands of wine and tuna fish. Moreover, the influence of water volume on the leaching of elements in the mate tea as well as the inhomogeneity of coffee beans and wine stoppers were studied.

In this paper, a Brazilian roasted ground coffee from a popular brand was analyzed using particle-induced X-ray emission (PIXE). The elemental analysis identified elements such as Mg, Al, Si, P, S, K, Ca, Ti, Mn, Fe, Cu, Zn and Rb. While K, Mg and P are major elements, Mn, Fe, Zn and Rb were found in trace amounts. The presence of rubidium as a trace element in the samples is discussed in view of its presence in Brazilian coffee, soil and other beverages.

Nine gold-plated costume jewelries bought in the street market of Porto Alegre and from Chinese websites were investigated through Particle-Induced X-ray Emission (PIXE) and Rutherford Backscattering Spectrometry (RBS) in order to verify their elemental composition and distribution. The analyzed costume jewelries were made of Cu-based alloys with Ni, Zn, Sn and Al. Elements such as Ag, Al, Bi, Cd, Co and Fe were found in minor amounts in some particular samples. Through RBS, it was possible to distinguish the bulk from the gold-plated layer. Toxic elements as Ni and Cd were found in at least one sample. The high concentration of Ni comes from the bulk Cu-alloy below the Au layer. In this case, the Au acts as a protective layer separating the Ni from the user’s skin.

Three tree core samples of Norway spruce (Picea Abies) have been analysed by PIXE. The concentration profiles for 17 elements heavier than sodium have been determined by means of one PIXE measurement every 2 mm along the samples. The samples were collected at Fäxboda, an experimental area north of Uppsala where artificially acidified and limed environmental experiments are made. One sample from each of an acidified, a limed and a reference area has been collected. The main interest is focused on potassium, calcium, manganese, iron, copper and zinc.

All three samples have about the same concentration profile in the heartwood. Large differences are observed in the sapwood. In the sample from the limed area the calcium content is much higher and the iron and chromium. contents are lower than in the sample from the reference area. In the sample from the acidified area the calcium and potassium contents are lower and the manganese, iron and chromium contents are much higher than in the sample from the reference area.

The observed concentration profiles of trace elements in trees indicate that changes in the environment due to acidification can be quantified at an early stage by means of PIXE.

A method of quantitative analysis of bone samples by simultaneous measurements of proton induced X-ray emission (PIXE) and Rutherford backscattered (RBS) spectra is described. The method is used for the evaluation of the data collected during proton microprobe irradiation. The RBS spectra are used for the determination of the sample thickness. The sample matrix is regarded as a mixture of collagen and hydroxyapatite. The unknown proportion of both compounds at each irradiated point is adjusted until the Ca concentration determined by PIXE is in accordance with the value calculated on the basis of the assumed matrix composition. For quantitative analysis, the calculation of the absolute yield using the thick target PIXE formula was applied. The sources and ranges of systematic errors are discussed.

Indoor dustfall samples were collected in Pit 1 and Pit 2 of Emperor Qin's Terra-cotta Warriors and Horses Museum in Xi'an, Shaanxi Province, China. The morphological and elemental analysis for long-term (>10 years) and short-term (~0.5 year) dustfall particles and lacquer pieces on the faces of partly assembled warriors were performed with scanning electron microscopy with energy dispersive X-ray spectrometer (SEM/EDX). The results showed that the majority of dustfall samples appeared to be composed of mineral dust particles, fly ash, and biological particles with different elemental compositions. Most of the mineral particles had irregular shapes with smooth edges. Small floccules of calcium sulfate were more frequently observed in long-term dustfall samples than in short-term samples, implying a progressive chemical reaction between continuous dustfall particles and atmospheric sulfur dioxide. Crystals of calcium sulfate were also found near pits on both inner and outer surfaces of lacquer pieces, revealing an acid chemical reaction between sulfur dioxide and lacquer material as the cause of the formation of erosion pits and cracks on surface of lacquer pieces.