Microbeam Particle-induced X-ray Emission Research Articles

Study on chemical forms of aluminum in tea leaves using micro-PIXE method

Elemental analysis of the epidermis of tea leaves was performed using the micro-beam particle-induced X-ray emission (micro-PIXE) method. The ratios of the X-ray yields of silicon (Si), potassium (K), calcium (Ca), and manganese (Mn) to that of aluminum (Al) in the cell wall of epidermal cells of tea leaves were determined. The ratio of Si to Al X-ray yields agreed within a range of 11% in the four samples measured in this study. On the other hand, the ratio of the X-ray yields of K, Ca, and Mn to Al varied from 41% to 87%. This result suggests that Al forms compounds with Si in tea leaves.

MeV-proton capillary microbeam PIXE mapping study of solution diffusion in paper

A tapered glass capillary MeV-ion microbeam setup, previously home-developed, was recently upgraded. To check the upgraded microbeam system quality and accuracy, microbeam particle induced X-ray emission (PIXE) mapping of potassium permanganate (KMnO4) solution diffusion in filter paper was carried out to study how the measured solvent diffusion followed the diffusion laws. Two initial boundary conditions and diffusion situations were applied: (1) the paper vertically placed in air with one end soaked in the solution for ten minutes, and (2) the paper horizontally placed on water with the solution dropped at a side of the paper for three minutes. 2-MeV-proton microbeam PIXE analyzed the paper pixel by pixel and the GUPIXWIN software was used to calculate the elemental concentrations in the pixels to map the concentration changes in the pixels as a function of the distance between the pixel position and the origin of the solution. The resulting maps demonstrated the solution diffusions in two cases indeed well following the diffusion laws, a steady-state diffusion dominated process where the elemental concentration was a linear function with the distance but joined by other non-diffusion factors for case 1, and a pure diffusion process where the elemental concentration was an error function with the distance for case 2.

Metallomics in deep time and the influence of ocean chemistry on the metabolic landscapes of Earth\u2019s earliest ecosystems

Modern biological dependency on trace elements is proposed to be a consequence of their enrichment in the habitats of early life together with Earth’s evolving physicochemical conditions; the resulting metallic biological complement is termed the metallome. Herein, we detail a protocol for describing metallomes in deep time, with applications to the earliest fossil record. Our approach extends the metallome record by more than 3 Ga and provides a novel, non-destructive method of estimating biogenicity in the absence of cellular preservation. Using microbeam particle-induced X-ray emission (µPIXE), we spatially quantify transition metals and metalloids within organic material from 3.33 billion-year-old cherts of the Barberton greenstone belt, and demonstrate that elements key to anaerobic prokaryotic molecular nanomachines, including Fe, V, Ni, As and Co, are enriched within carbonaceous material. Moreover, Mo and Zn, likely incorporated into enzymes only after the Great Oxygenation Event, are either absent or present at concentrations below the limit of detection of µPIXE, suggesting minor biological utilisation in this environmental setting. Scanning and transmission electron microscopy demonstrates that metal enrichments do not arise from accumulation in nanomineral phases and thus unambiguously reflect the primary composition of the carbonaceous material. This carbonaceous material also has δ13C between −41.3‰ and 0.03‰, dominantly −21.0‰ to −11.5‰, consistent with biological fractionation and mostly within a restricted range inconsistent with abiotic processes. Considering spatially quantified trace metal enrichments and negative δ13C fractionations together, we propose that, although lacking cellular preservation, this organic material has biological origins and, moreover, that its precursor metabolism may be estimated from the fossilised “palaeo-metallome”. Enriched Fe, V, Ni and Co, together with petrographic context, suggests that this kerogen reflects the remnants of a lithotrophic or organotrophic consortium cycling methane or nitrogen. Palaeo-metallome compositions could be used to deduce the metabolic networks of Earth’s earliest ecosystems and, potentially, as a biosignature for evaluating the origin of preserved organic materials found on Mars.

Localization of Aluminum in Epidermal Cells of Mature Tea Leaves

We have determined the distribution of aluminum in the epidermal cells of mature tea leaves using micro-beam particle-induced X-ray emission. The observed pattern of aluminum distribution in the epidermal cells suggests that aluminum exists in cell walls. Silicon exhibits a distribution that is nearly identical to that of aluminum, suggesting co-localization with aluminum.

Lithium distribution analysis in all-solid-state lithium battery using microbeam particle-induced X-ray emission and particle-induced gamma-ray emission techniques

For confirming the feasibility of micrometer scale analysis of lithium distribution in the all-solid-state lithium battery using a sulfide-based solid electrolyte, the cross-section of pellet type battery was analyzed by microbeam particle-induced X-ray emission (PIXE) and particle-induced gamma-ray emission (PIGE) measurements. A three-layered pellet-type battery (cathode: LiNbO3-coated [Formula: see text]/solid electrolyte: [Formula: see text]/anode: [Formula: see text]) was prepared for the measurements. Via elemental mapping of the cross-section of the prepared battery, the difference in the yields of gamma rays from the [Formula: see text] inelastic scattering (i.e., the lithium concentrations) between the composite electrodes and the solid electrolyte layer was clarified. The difference in the number of lithium ions at the composite anode/solid electrolyte interface of ([Formula: see text] mol) in the battery can be clearly detected by the microbeam PIGE technique. Therefore, lithium distribution analysis with a micrometer-scale spatial resolution is demonstrated. Further analysis of the cathode/anode composite electrodes with the different states of charge could provide important information to design a composite for high-performance all-solid-state lithium batteries.

Interpretation of the Chemical Transformation of Individual Asian Dust Particles Collected on the Western Coast of Korean Peninsula

This paper is focused on the comprehensive and detailed interpretation for the chemical transformation of individual Asian dust (hereafter called "AD") particles during long-range transport from source regions to receptor area. A multi-stage particle sampler was operated at a ground-based site in Taean, Korea directly exposed to the outflow of air masses from China during AD period in April 2003. Both quantitative and qualitative analyses for size-classified individual particles were carried out by a microbeam X-ray fluorescence (XRF) method and a microbeam Particle Induced X-ray Emission (micro-PIXE), respectively. Among major characteristic elements, the elemental masses of soil derived components, sulfur, and chloride varied as a function of particle size showing the monomodal maximum with a steeply increasing at 3.3-4.7 <TEX>${\mu}m$</TEX> particle size. Although the details on chemical composition of AD particle collected on a straight line from source area to our ground-based site are needed, a large amount of Cl coexisted in and/or on AD particles suggests that AD particles collected in the present study might be actively engaged in chemical transformation by sea-salt and other Cl containing pollutants emitted from the China's domestic sources. Through the statistical analyses it was possible to classify individual AD particles into six distinct groups. The internally mixed AD particles with Cl, which has various sources (e.g., sea-salt, coal combustion origin HCl, gaseous HCl derived from the adsorption of acids to sea-salt, and Cl containing man-made particles) were thoroughly fractionated by the elemental spectra drivened by the double detector system of micro-PIXE.

Raising the temper—μ-spot analysis of temper inclusions in experimental ceramics

Provenancing of ancient ceramics is a highly important scientific tool for archaeological studies. In general, ceramics are not made from the original clay as it is found in deposits. To produce the needed physical properties in the finished product, the clay has to be either tempered by adding sands or biological materials, or levigated, to remove the coarse fraction. Thus, the chemical composition of the finished ceramic differs from the composition of the original clay bed. To overcome this obfuscation, any information that can be gained about the temper is useful. In a small series, several pieces of ceramic were produced from known clay and tempers and the resulting ceramics analysed by neutron activation analysis (NAA). As many attempts to physically separate the temper from the clay matrix have failed, μ-spot analysis of temper inclusions was performed at the microbeam particle induced X-ray Emission (μ-PIXE) facility in Rossendorf and with laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS) at the Aberystwyth University in Wales. It could be shown that from a small number of measurements, a general impression of the temper used could be gained. Furthermore the μ-spot methods and the bulk data gained from INAA are highly comparable, extending the set of elements that can be measured. With this information, the influence of the temper on the bulk composition of the finished product can be estimated, which potentially adds crucial information to subsequent dilution calculations.

Corrosion of 15th and early 16th century stained glass from the monastery of Batalha studied with external ion beam

This paper reports the study of corrosion in two stained glass panels from the south aisle of Sta. Maria da Vitória monastery, at Batalha (Portugal), one depicting the Last Supper (dated from 1508), and the other one showing a saint (c. 1450). These panels exhibit extensive corrosion with darkening phenomena that are an impediment to their correct visualization, a source of major concern both to conservators and curators. By using external micro-beam Particle Induced X-ray Emission (PIXE) and Particle Induced Gamma Emission (PIGE) spectrometry, the elemental compositions of large fragments were obtained, enabling the selection of representative corroded areas, from which elemental distribution maps were produced by scanning. Calcium and potassium rich structures were found – at the surface and inside cavities in the glass – that were identified as oxalates and carbonates, by Raman microscopy and micro-FTIR. The dark spots present in the glass surfaces were found to be Zn and Pb rich. These findings indicate that the corrosion observed was due not only to reactions with atmospheric water and CO 2 but also with the oxalic acid secreted by micro-organisms. Furthermore, it did not result from reactions with atmospheric SO 2 or acid rain. The information obtained is relevant for a better understanding of the corrosion processes and products formed on the surface of these panels and therefore for the proper planning of much needed adequate conservation–restoration actions and appropriate display conditions.

Proton µ‐PIXE mapping, AFM imaging and size statistics of mineral granules in a dental composite

AbstractWe applied proton microbeam particle‐induced X‐ray emission (µ‐PIXE) for mapping Ca, Zr, Ba and Yb, and atomic force microscopy (AFM) for imaging the surface landscape of a dental composite which releases Ca2+ and F− for the protection of hard dental tissues. Three areas ∼250 × 250 µm2 located ∼0.5–2 mm apart on a smooth surface specimen were mapped with 3.1 MeV protons focused to a ∼3.0 µm spot and at ∼3.9 µm pixel size sampling. The maps evidenced particles with diameters of 3.2–32 µm (Ca), 20–60 µm (Zr), ≤ 4 µm (Ba) and 10–50 µm (Yb). Cross‐section area histograms of Ca‐rich particles fitted with 2–6 Poisson functions revealed a polydisperse size distribution and substantial differences from an area to another, possibly implying large local variations of Ca2+ released in the hard tissue near a dental filling of a few millimeters in diameter. Such imbalances may lead to low local Ca2+ protection of the dental tissue, favoring the onset of secondary caries. Similarly, AFM images showed high zone‐dependent differences in the distributions of grains with apparent diameters of 1–4 µm, plausibly recognized as Ca‐ and Ba‐containing particles. In a simple model based on demineralization data, lateral diffusion of Ca2+ between adjacent domains containing high‐ and low‐area Ca‐rich grains is described by exponential concentration gradients. These gradients may generate appreciable electromotive forces, which may enhance electrochemically the local tissue demineralization. Similar effects are to be expected in the protective action of F− ions released from microgranules of YbF3 and of Ba fluoroaluminosilicate glass. Copyright © 2010 John Wiley &amp; Sons, Ltd.

Stained glasses under the nuclear microprobe: A window into history

Stained glass fragments from the 15th, 16th and 20th centuries, belonging to Mosteiro de Santa Maria da Vitória, Batalha (Portugal), were characterised non-destructively in a nuclear microprobe. The work aimed at finding the composition of the glasses and glass paintings and relating these with the corresponding production periods. The elemental compositions of the glass fragments were obtained by means of scanning micro-beam Particle Induced X-ray Emission (μ-PIXE) spectrometry in selected cross-sections. These were complemented by micro X-Ray fluorescence spectrometry. Characterisation of colour was performed by optical absorption spectroscopy in the UV–vis range, while the corrosion products were identified by optical microscopy and μ-FTIR (Fourier Transform Infra Red) spectroscopy in combination with the data generated by μ-PIXE. Nuclear microprobe analysis allowed unveiling the compositions and structures, in particular of glass paintings and corrosion products. While it is not surprising that Fe, Cu and Pb were the main elements identified in the grisaille paintings of all studied periods, as well as Ag and Cu found in the glasses decorated with yellow silver painting, their distribution gave important clues on the materials and techniques used to manufacture these stained glasses. Furthermore, it allowed establishing a definite relation between the compositions found and the periods of production, with the added bonus of correctly reassigning the manufacturing period of some samples.

Stained glasses from Monastery of Batalha: Non-destructive characterisation of glasses and glass paintings

Abstract The characterisation of stained glass fragments belonging to the lateral north wing, to the Capela-Mor and to the Capela do Fundador of the Monastery of Santa Maria da Vitoria, Batalha, Portugal, was performed by non-destructive analyses. The work aimed at finding the composition of the glasses and decorations, and relating these with the corresponding production periods. The chemical compositions of the glass fragments were obtained by micro X-Ray Fluorescence Analysis (μ-XRF), completed with the distribution maps obtained from selected cross-sections by means of micro-beam Particle Induced X-ray Emission Analysis (μ-PIXE). Colour characterisation was performed by optical absorption spectroscopy in the UV–vis range, while corrosion products were characterised with optical microscopy and μ-Raman. The combination of the different analyses on the different glass samples allowed knowing the composition of the glasses and glass paintings. Using UV–vis spectroscopy, both the oxidation state of an element and its coordination, which are responsible for the colours displayed, could be determined. The presence and distribution of silver and copper in glass surfaces painted with yellow silver stain were also studied.

ELEMENTAL IMAGING IN PANCREAS OF IMMATURE RATS BY MICRO PIXE ANALYSIS

The pancreas is a large gland capable of both exocrine and endocrine functions; it releases digestive enzymes into the duodenum and hormones into the bloodstream. It is known that Zn plays a key role in the synthesis and action of insulin, one of the pancreatic hormones. However, elemental profiles of the pancreas are not well understood. Here, we examined precise distributions of elements in the pancreas of newborn and young rats by scanning microbeam particle induced X-ray emission (micro PIXE) analysis and compared the results to those of adult animals. Micro PIXE analysis revealed a site-specific distribution of elements in the two major compartments of the pancreas, the exocrine (acinar tissue) and the endocrine portions (islets of Langerhans). The Zn concentrations in the pancreas of the newborn (six days), young (three weeks), and adult rats (ten weeks) were 11.3 ± 2.5 μ g / g wet weight, 7.26 ± 0.36 μ g / g wet weight, and 10.8 ± 1.1 μ g / g wet weight, respectively. In newborn and young rats, Zn was detected mainly in the islets of Langerhans, while K and P were distributed more to the acinar tissues than the islet cells. The site-specific distributions of K , P , and Zn were more obvious in the adult animals.

Micro-PIXE and histochemical studies of Zn and Ca distribution in normal bone

To better understand the role of zinc in bone mineralization we studied the distribution of Ca and Zn by microbeam particle-induced X-ray emission (μ-PIXE) profiling and mapping, and of Zn by histochemical mapping and profiling in cortical bovine bone. For μ-PIXE, measurements were carried out at the Rossendorf nuclear microprobe with a 3.1MeV proton beam focused to a spot of ∼3μm, at ∼4–8μm effective resolution. Maps, unique scans and side-to-side scan sequences were done for Ca and Zn. The noise in Zn profiles was filtered by Fast Fourier Transform (FFT). For histochemistry, Zn was stained in thick sections by the sulphide-silver reaction. Both μ-PIXE and histochemistry showed that Zn was localized mainly at the surfaces of various structures in bone tissue.

On the Chemical Purity of Marine Microfossils

As a paleontologist, I was pleased to see the 35-million-year-old shell of the planktonic foraminiferan Cribrohantkenina inflata grace the cover of Physics Today ( Physics Today 0031-9228 54 12 2001 16 https://doi.org/10.1063/1.1445530. December 2001; story on page 16 ). Calcium carbonate–secreting microfossils are a powerful proxy for estimating sea-surface temperature change through time using stable oxygen isotopes. Another challenge that biogeochemists and geoscientists face is the alteration of in vivo isotopic values by mineral and chemical changes after an organism’s death. Implicit in any isotopic analysis using calcite shells, or fossil mammal teeth, or even dinosaur bones, is the assumption that the original stable isotopes survived the passage of millions of years.A hemisphere away from the late Cretaceous marine localities of Paul Pearson’s work, 1 1. P. Pearson, et al. , Nature 413, 481 (2001). https://doi.org/10.1038/35097000 dinosaur bones lie buried in late Cretaceous clays above the Arctic Circle on the North Slope of Alaska. 2 2. W. A. Clemens, L. G. Nelms, Geology 21, 503 (1993). https://doi.org/10.1130/0091-7613(1993)021<0503:PIOATV>2.3.CO;2 They are so well preserved that an oil geologist in the 1960s originally identified them as the fossil remains of Ice Age mammals. A collection of those bones is cataloged in the University of California Museum of Paleontology. Under high magnification, the Alaska fossils reveal a beautifully preserved system of bone cells that are identical to the micron-scale architecture of a modern vertebrate bone. Similar to the Pearson group’s foraminifera, the dinosaur bones are entombed in clay sediments and do not appear altered by secondary remineralization or recrystallization. Microbeam particle-induced x-ray emission analysis revealed, however, that the bones showed significant postmortem enrichment by metals, primarily iron and manganese, more than 104 times greater than in the bones of modern crocodilians and birds (a dinosaur’s closest living relatives). 3 3. M. B. Goodwin, G. S. Bench, J. Vertebr. Paleontol. 20(3), 45A (2000). Clay surrounding the Alaska dinosaurs was also markedly enriched in these metals from the burial environment.Understandably, such factors are site specific and most likely vary by sediment layer and location. Their range and potential influence on a paleobiological isotopic signature remains largely unknown. Until that situation changes, the potential alteration of stable isotope values in fossil shells, bones, and teeth prevents the rejection of the null hypothesis that all fossil material is altered.Beauty is in the eye of the beholder, and exceptional fossil preservation, even at the micron level, does not guarantee pristine chemistry.REFERENCESSection:ChooseTop of pageREFERENCES <<CITING ARTICLES1. P. Pearson, et al. , Nature 413, 481 (2001). https://doi.org/10.1038/35097000 , Google ScholarCrossref2. W. A. Clemens, L. G. Nelms, Geology 21, 503 (1993). https://doi.org/10.1130/0091-7613(1993)021<0503:PIOATV>2.3.CO;2 , Google ScholarCrossref3. M. B. Goodwin, G. S. Bench, J. Vertebr. Paleontol. 20(3), 45A (2000). Google Scholar© 2002 American Institute of Physics.

Na 4Lu(III)HDOTP as extracellular marker in indirect mapping of intracellular ion levels in heart tissue via microbeam PIXE

The determination of intracellular elemental concentrations in cryo-sections of cardiac tissue is influenced by the presence of extracellular space (ECS). Intracellular elemental concentrations are determined by using a perfusion buffer with Na 4Lu(III)HDOTP as an extracellular marker, thus making it possible to correct for the ECS. Results show that when a regular perfusion buffer is replaced by a buffer containing 5 mM Na 4Lu(III)HDOTP, the contractility of an isolated perfused rat heart reduces but recovers completely within a few minutes. The high sensitivity of particle-induced X-ray emission (PIXE) for Lu and the possibility to add high concentrations of the Lu-buffer without significant physiological effects enables mapping of intracellular elemental concentrations in heart tissue.

Quantitative particle-induced X-ray emission imaging of rat olfactory epithelium applied to the permeability of rat epithelium to inhaled aluminum.

Neurotoxicity from chronic metal inhalation has been suggested as an underlying contributor to late-developing neurodegenerative diseases that have symptoms similar to Alzheimer's and Parkinson's syndromes. If inhaled metals contribute to pathogenesis of these diseases, identifying, localizing, and quantitating metal deposition(s) within specific target regions of the central nervous system will be critical to our understanding of the mechanisms. Standard analytical techniques used to date require exposure to extremely high concentrations of metals to meet analytical detection limits in small tissue areas. The relevance to lower-dose environmentally relevant exposures and potential protective barriers is therefore questionable. The feasibility of microbeam particle-induced X-ray emission is investigated as a method for rapidly scanning tissues to study the inhalation of metals, nasal permeability, and central nervous system deposition. The optimal beam spot and analysis time used to image the rat olfactory epithelium to facilitate the rapid detection of aluminum localizations were determined. Measurements of aluminum localizations in rat olfactory bulb and brain sections are also presented.

Wear studies of tungsten carbide cutting tools using the Micro-PIXE technique

The rake and flank faces of worn tungsten carbide cutting tools used to machine BS EN1A steel were analyzed using micro-beam particle induced X-ray emission (Micro-PIXE) technique. The distribution maps of the workpiece material elements (Fe and Mn) and the tool material element (W) on the tool faces were constructed and used to determine the geometry of the wear regions on the cutting tools. These wear regions agreed very well with those observed by the scanning electron microscope (SEM). The results showed lack of correlation between the distributions of Fe and Mn. The distribution of Mn indicates the presence of diffusion wear whereas the distribution of Fe shows the presence of adhesive wear. Micro-PIXE has assisted in understanding the nature of tool wear and identifying the prevailing wear mechanisms.