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Abstract  

This study is a one-year monitoring of the inhalable particulate matter (PM10) of Shanghai (from January 2006 to December 2006) to study PM10 pollution. Proton-induced X-ray emission (PIXE) was used to investigate the chemical elements in Shanghai PM10. The study finds seasonal variation in both mass concentration and of chemical elements in PM10. The results of the enrichment factor show that the chemical elements in the inhalable particles could be divided into two categories, soil elements from earth crust and anthropogenic pollution elements. The high enrichment factors suggest that anthropogenic activities were the dominant source for elements such as S, Cu, Cl, Zn, Pb and Br. Strong correlation of K, Ca, Fe and Ti, from factor analysis, indicates these elements coming from earth crust or soil, S, Zn and Pb from industrial pollution and/or traffic and Cl from coal combustion.

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Abstract  

Two different modes of sample excitation have been used for elemental analysis of thin standard reference materials and of chemical standards with known composition. PIXE /2.5 MeV protons/ and XRF induced by PIXE, will be called XRF-PIXE /2.5 MeV protons on Mo primary target/. The same samples were alternatively exposed to protons and X-ray beams. The sensitivities under standard running conditions are determined for both an XRF-PIXE and a PIXE analysis system. It is shown that the sensitivity of the PIXE spectrometer depends strongly on the sample matrix, whereas the XRF-PIXE sensitivity is rather constant with respect to different kinds of samples. In addition, the advantages of one mode of excitation on the other are discussed. It is shown that XRF-PIXE can be a useful complement to PIXE analysis.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Jimenez-Reyes, D. Tenorio, E. Martinez-Quiroz, and A. Sanchez-Ocampo

Abstract  

Allanites from Telixtlahuaca (Oaxaca, Mexico) were analyzed using the PIXE technique. The concentrations of 12 elements, mainly rare earths, were determined.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Oksanen, J. Meriläinen, J. Räisänen, T. Saarinen, and A. Virtanen

Abstract  

The feasibility of the particle induced X-ray emission (PIXE) technique for varve counting of vertically taken marine and lacustrine sediments was studied aiming at its possible use as a dating procedure by observing the yearly variation of the constituent elements. The samples were impregnated with a low viscosity epoxy resin to obtain slabs with preserved layered structure suitable for the PIXE analyses. PIXE-spectra were taken as a function of depth distance and the normalized X-ray peak area variations were determined. Especially, concentration changes of silicon and iron were found to be clear. Due to the employed sample preparation technique the observed chlorine concentration corresponds to the amount of water in the initial sample. Maximum chlorine concentration appeared at positions where the Si and Fe concentrations were near minimum. By plotting the Si/Cl or Fe/Cl peak area ratios, an even more distinct position dependent variation was noted.

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Abstract  

An accelerator-based elemental study, using proton-induced x-ray emission (PIXE), was performed on four full-cream and four half-cream brands of powdered milk commonly consumed in Jordan. The elements detected in the samples are S, Cl, K, Ca, Fe, Cu, Zn, Br, and Rb. The significance of some of these elements is discussed from the viewpoint of nutrition and also their effect on milk processing and dairy technology. The standard reference milk sample, A-11, which is distributed by IAEA was also examined, and the results for trace elements detected are compared with the values certified by IAEA.

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Abstract  

PIXE analysis method is applied to archaeometry problems. Advantages and disadvantages are emphasized. Some examples are presented which show the difficulties; especially important heterogeneities of ceramics, old coins and metals restrain from the use of this technique: other analysis systems, less expensive, like electron microprobe or X-ray fluorescence spectrometry, are compared with conventional PIXE method. The importance of proton microprobe is explained.

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Abstract  

The capabilities of a standard multiparametric fitting procedure for extracting concentration profiles from a set of PIXE yield measurements are evaluated for both: real Zn depletion profiles in an initially homogeneous Ag 3 at % Zn alloy, annealed under vacuum, and simulated sinusoidal profiles. The comparison with the profiles obtained via iteration plus smoothing shows that multiparametric fitting is more performing.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Olabanji, A. Haque, S. Fazinic, R. Cherubini, and G. Moschini

Abstract  

As a rapidly growing vast country, there is need in Nigeria to develop alternative energy sources to meet its ever increasing energy demands. Tar sands apart from its popular use as a source of asphaltic material for road surfacing is a new energy raw material in Nigeria. The immense industrial applications and utilization of the by-products of tar sands provide great incentives for its development. PIGE and PIXE techniques were employed for the determination of the major, minor and trace elemental concentrations in Nigerian tar sands including sulfur which occurs as pyrites, organic sulfur and sulfates. Proton beams produced by the 7 MV CN and 2.5 MV AN 200 Van de Graaff accelerators at I.N.F.N. Laboratori Nazionali di Legnaro (LNL) at Padova, Italy, were used for the PIGE and PIXE analysis, respectively. Results of this novel study are presented, discussed, and compared with some data from previous worker and values from Athabasca (Canada).

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Abstract  

The method of thin film PIXE was applied to the analysis of a total of 117 urine specimens from urinary stone sufferers and controls. The overall range of Br levels was between 2 and 18 g cm–3. Mean values obtained over a period of three days ranged from 6.8 to 9.2 g cm–3. No significant differences between the Br distributions in the two groups over the collection period were observed.

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Abstract  

A rapid method is described for simultaneous trace determination of metallic impurities in lithium metal by Particle Induced X-ray Emission (PIXE) technique. The impurities were preconcentrated by ion-exchange separation using a weak cation exchanger, Bio Rex-70 and analyzed by 2.34 MeV protons. The reliability of the method was tested by analyzing synthetic samples having several metallic impurities at 1–5 ppm range.

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