The proton induced K X-ray emission spectra of several different phosphorus and sulfur compounds were recorded with the new parallel-beam wavelength dispersive X-ray emission spectrometer. The ...spectrometer was installed recently at the external proton microbeam at the J. Stefan Institute to perform high energy resolution in-air micro-PIXE analysis in the tender X-ray range. Reported measurements are used to probe the capabilities of the spectrometer to perform also chemical state analysis. For phosphorus measurements, where the energy resolution of the spectrometer is the highest, a clear correlation between measured energy position of the Kα emission line and the phosphorus formal oxidation state is obtained. Chemical contrast is increased further in the Kβ emission spectra reflecting the structure of occupied valence molecular orbitals defined by the first coordination shell around the central phosphorus atom. A reasonable chemical contrast is maintained also in the sulfur Kβ emission spectra, despite the fact that the energy resolution of the spectrometer declines with increasing X-ray energy. Finally, an example of phosphorus speciation in reference biological material is presented, demonstrating the feasibility of the new setup to extend the capabilities of in-air micro-PIXE analysis towards chemical speciation.
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•The PB-WDS X-ray emission spectrometer was used to perform chemical state analysis of P and S.•Measured phosphorus Kα emission spectra exhibit energy shifts correlated with the formal oxidation state.•Kβ emission spectra of P and S reflect the coordination of neighboring atoms bound to the central phosphorus or sulfur atom.•The phosphorus spectra collected from standard reference biological material was used to specify its chemical state as a phosphate.
An adsorbent used for the recovery of trivalent minor actinides (MA(III); Am and Cm) from high level liquid waste generated from reprocessing of spent nuclear fuel was subjected to micro-particle ...induced X-ray emission (micro-PIXE) analysis to improve its elution performance. The experimental adsorbent comprised SiO2 particles, a polymer coating, and an N,N,N′,N′-tetraoctyl diglycolamide (TODGA). The particles to be analyzed were subjected to Nd adsorption and an elution operation, but Nd in the adsorbent was found to be uniformly distributed. This might have been caused by individual differences in the amount of impregnated TODGA. The remaining Nd species were not localized to a specific part of the adsorbent after the adsorption operation. Some Nd elements were retained in the adsorbent after elution, probably because of the poor diffusion of the mobile phase inside the adsorbent. An adsorbent having a different microstructure from the first was then evaluated, and rapid elution was observed on new adsorbent along micro-PIXE analysis.
•Generally, an adsorbent performance is evaluated with a chemical test.•Micro-PIXE is applied for evaluation of a SiO2-adsorbent performance.•A problem of an adsorbent's performance is solved by micro-PIXE analysis.
When charged particles collide with atoms, atomic inner shell electrons become ionized, producing characteristic X-rays. This phenomenon is called particle-induced X-ray emission (PIXE). The ...characteristic X-ray production cross-sections from PIXE are very large, and the characteristic X-rays of elements contained in a sample are easily measured by a Silicon detector with a high energy resolution. Hence, sodium to uranium can be detected with a sensitivity of ppb~ppm, and PIXE has been applied to trace element analysis. Scanning ion beams can be used to obtain the spatial distributions of elements in a sample. Furthermore, the distributions of elements inside a cell can be investigated using micro ion beams. PIXE analysis is a very useful technique for multi-elemental analysis and is now widely used in many fields and applications, including chemistry, medicine, biology, archaeology, agriculture, materials science, fisheries science, geology, petrology, environmental study, contamination monitoring, resource search, semiconductors, metal, astrophysics, earth science, criminal investigations, and food.
Concentrations of copper (Cu), iron (Fe) and zinc (Zn) were measured in the rims and cores of senile plaques (SP) and in the neuropil of the amygdala of nine Alzheimer's disease (AD) patients and in ...the neuropil of the amygdala of five neurologically normal control subjects using micro particle-induced X-ray emission (micro-PIXE). Comparison of SP rim and core values revealed no significant differences between levels of Cu, Fe or Zn. Zinc and Fe in SP rims and cores were significantly elevated in AD compared with AD neuropil (
P<0.05). Copper was significantly elevated (
P<0.05) in the rim of SP compared with AD neuropil. Comparison of AD and control neuropil revealed a significant (
P<0.05) elevation of Zn in AD subjects. The elevation of these elements in SP in AD is of interest in light of the observation that Cu, Fe and particularly Zn, can accelerate aggregation of amyloid beta peptide.
Interstitial pneumonia develops in association with inhaled particles. In-air microparticle induced X-ray emission (in-air micro) analysis was previously employed to assess the spatial distribution ...and content of particles in surgical lung biopsy specimens. The aim of this study was to assess the efficacy of in-air micro-analysis for transbronchial lung biopsy specimens in patients with or without occupational exposure. The elements composing lung particles and their locations could be identified by in-air micro-analysis. Silicon was the major component of particles. Quantitative analysis revealed that the elements composing lung particles varied between patients. In a patient with suspected nickel exposure, aluminium, vanadium, and calcium were detected, but was not detected. In a patient without a work history (housewife), various elements were detected. In-air micro-analysis was useful for assessing the spatial distribution and content of particles in specimens from patients. Occupational exposure was not necessarily associated with deposition of particles in the lungs. Therefore, in the diagnosis of, elemental analysis of specimens by in-air micro-analysis could be useful for assessing exposure to particles objectively.
Elemental analysis of cellular samples by in-air micro-PIXE Ishii, K; Sugimoto, A; Tanaka, A ...
Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms,
07/2001, Letnik:
181, Številka:
1
Journal Article
Recenzirano
We developed a micro-PIXE system for the analysis of frozen cellular samples at atmospheric pressure under helium gas cooling. We analyzed bovine aortic endothelial (BAE) cells previously cultured in ...a medium containing bromodeoxyuridine (BrdU). It is known that these cells take BrdU into their nuclei at the S phase of their metabolic cycle. We examined the Br uptake for incubation times of 6, 12 and 24 h, respectively. The Br maps showed an accumulation in the nuclei and the Br concentration was found strongly dependent on the incubation time. We have demonstrated that in-air micro-PIXE analysis is a relevant technique for examining the molecular uptake in cells.
An 81-year-old Japanese man had organizing pneumonia (OP), and he had worked as a painter and had a history of exposure of various paints over 20 years. The major features on computed tomography (CT) ...in patients were cryptogenic organizing pneumonia (COP) showing airspace consolidation, and air bronchograms were consistent finding in consolidation in right lung of S10. Such parenchymal abnormalities were clinically and pathologically diagnosed COP and the lesion was improved by corticosteroid therapy. About 1.5 years later, similar shadows emerged in new locations of right S4 and left S8, and these were bronchioloalveolar carcinoma (BAC) classified as adenocarcinoma. BAC causes similar X-ray changes to COP and inflammation accompanying BAC can also respond to corticosteroids, which may lead to delay in the diagnosis of BAC associated with COP. These radiological features lead to difficulty in making a diagnosis of new parenchymal diseases. The present patient had been painter, and metals of carcinogens were proven in both tissue of COP and BAC. Here, we reported a painter with COP and new-onset BAC who had been exposed to particles proven by elemental analysis. The combination of COP with BAC is considered uncommon, but the risk of BAC may increase when there is a history of particle inhalation.
We developed a novel technique to obtain 3D-imaging of elemental distribution based on multi-angle RBS measurement and micro-beam scanning. Since cross-sections of RBS are too small to obtain ...3D-imaging, it is necessary to measure scattered particles with large solid angle detectors. Hence, the RBS profiles from each scattering angle are superposed and a true depth profile cannot be obtained. Recently, a large solid angle X-ray detector array consisting of 45 detector elements was installed at the TIARA facility of Japan Energy Research Institute. Each detector element measures X-rays as well as scattered particles. For this utilization, we introduced a technique to superpose RBS profiles and applied it to the surface analysis of an ant’s head.
To characterize the physical and chemical properties of the individual aerosol particles during Asian dust storm in Japan, micro-PIXE technique was applied in this study. Aerosol particles were ...sampled in Kyoto, Japan from the middle of March to the end of April 1999. Mass concentration in Asian dust storm events was roughly 3–5 times higher than that of the highest concentration measured in non-Asian dust storm seasons. Single particles were generally sharp-edged and irregular in shape and contained mostly crustal elements such as Si, Fe and Ca. Although in soils of the desert and loess areas in northwest of China S and Cl were not detected, significant concentrations of S and Cl were detected in coarse fraction during Asian dust storm event. Nearly all single particles in the coarse fraction existed as a mixed state of soil components and S.
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