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The scanning nuclear microprobe of the Institute of Applied Physics of the National Academy of Sciences of Ukraine is an analytical channel based on the compact electrostatic accelerator "Sokol" of the Van de Graaff type with the maximum voltage at the high-voltage terminal of 2 MV and is designed for local non-destructive analysis of samples of various origins with high sensitivity (~1 ppm), as well as for the fabrication of three-dimensional small structures of high quality using proton beam writing. The resolution of the microprobe is about 3 μm with a beam current of I ~ 100 pA and 0.6 μm with I ~1 pA. The maximum scanning raster with a focused beam on the sample surface is 1 × 1 mm2. The microprobe implements the techniques of particle-induced X-ray emission, Rutherford backscattering, and secondary electron microscopy. The article also gives examples of the use of the nuclear microprobe in physical research.

Physiologically relevant concentrations in biological tissue, in the in vivo, state are of the order of μmol L−1 and mmol L−1. Up to the present, mapping the major elements in the matrix and its thickness has been neglected, despite their importance for quantification of lesser and trace element concentrations. Ryan and Jamieson's dynamic analysis, statistical spectral decomposition approach, is developed to quantitatively measure ex vivo tissue sections cut using a cryomicrotome. This mitigates the problem that physical analysis methods require a vacuum environment. This approach is used to quantitatively image the major matrix elements H, C, N, and O as well as trace maps of Ca, Fe, and Zn in a tissue section of porcine intestine. This sample is selected as it exhibits a complex morphology with multiple tissue compartments (such as muscle and mucosa, as well as void areas from blood vessels, lymph ducts, sinuses crypts, and villi. In the results, it is demonstrated that different tissue types can have a different matrix composition and thickness. Using this information, quantitative maps and elemental molarities for the lesser and trace elements Ca, Fe, and Zn are obtained. [ABSTRACT FROM AUTHOR]

The scanning nuclear microprobe of the Institute of Applied Physics of the National Academy of Sciences of Ukraine is an analytical channel based on the compact electrostatic accelerator “Sokol” of the Van de Graaff type with the maximum voltage at the high-voltage terminal of 2 MV and is designed for local non-destructive analysis of samples of various origins with high sensitivity (~1 ppm), as well as for the fabrication of three-dimensional small structures of high quality using proton beam writing. The resolution of the microprobe is about 3 μm with a beam current of I ~ 100 pA and 0.6 μm with I ~1 pA. The maximum scanning raster with a focused beam on the sample surface is 1 × 1 mm² . The microprobe implements the techniques of particle-induced X-ray emission, Rutherford backscattering, and secondary electron microscopy. The article also gives examples of the use of the nuclear microprobe in physical research. [ABSTRACT FROM AUTHOR]

Generally, particle-induced X-ray emission (PIXE) analysis is performed using protons as the incident projectiles. In this study, helium ions were used for inducing X-ray emission to improve the detection limit for the characterization of light elements in the PM2.5 fine fraction. The sampling was conducted for 24 h using a Gent stacked filter unit sampler at an industrial site in Surabaya, Indonesia. The samples were analyzed by PIXE using a 4-MV Van de Graaff accelerator at Kyoto University. Both helium and protons were used in the analysis to obtain optimal results, and 21 elements were detected in the samples. Notably, the use of helium particle-induced X-ray emission was more suitable for Na, Mg, Al, and Si than protons. Moreover, the sensitivity and limit of detection for these elements were enhanced using helium ions. Validation was performed using standard reference material NIST 2783 air particulates on filter media, and the results were in good agreement. Using both He-PIXE and H-PIXE, heavy metals, crustal elements, and other elements were identified that exhibited the characteristics of PM2.5 collected in Surabaya, Indonesia. Further statistical analysis and receptor modeling are required to identify the possible pollutant sources of PM2.5. [ABSTRACT FROM AUTHOR]

Pb-free electrical solders, such as Cu-Sn alloys, work well for reflow soldering under tightly controlled conditions. Hand soldering, however, often results in poor quality joints compared to conventional Pb-Sn solders. To investigate this under realistic workshop conditions, micro-particle induced X-ray emission (micro-PIXE) with 2 MeV protons has been employed. Commercial flux-cored Cu-Sn and Pb-Sn solder wires are studied. Solder blobs under two cooling conditions as well as tinning Restriction of Hazardous Substances (RoHS)- compliant and legacy component wires are investigated. The results show that the long heating and slow cooling of Cu-Sn solder blobs lead to formation of an acicular precipitate that can be ascribed to Cu6 Sn5. Pb-Sn solder under the same conditions shows phase separation with regions of high Sn and regions with high Pb. In the case of rapidly cooled blobs where a shiny surface is produced, no phase separation in either solder is observed. Tinning of RoHS-compliant and legacy Cu component wires with the two solders produce significantly different interfacial depth profiles with varying degrees of grading, indicative of intermetallic phase formation. [ABSTRACT FROM AUTHOR]

A porous silica-based adsorbent was prepared by impregnating the pores of a silica support with the extractant 1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-calix[4]arene (Calix[4]arene-R14) and an additive agent 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (C2mim + NTf2−) as the materials to remove cesium(I) (Cs+) ions from seawater. The as-prepared adsorbent showed excellent adsorption performance toward Cs+ ions, with adsorption equilibrium reached within 2 h and an adsorption amount of 0.196 mmol/g observed. The solution pH, temperature, and the presence of coexisting metal ions were found to have almost no effect on Cs+ adsorption. The adsorption mechanism was considered to proceed via ion exchange between Cs+ and C2mim+. In addition, the particle-induced X-ray emission analysis results further clarified that the adsorbed Cs+ ion species on the adsorbent was in the form of both CsCl and CsBr.

Energy crises and growing demand for energy has increased the importance of biodiesel from algae, because renewable, carbon neutral, transport fuels are necessary for environmental and economic sustainability. This study was undertaken to know the proper production of biodiesel from algae. The Spirogyra species of algae was used in the gasification process in the presence of catalyst. For this purpose cobalt/calcium oxide nanoparticles were prepared by co-precipitation, characterized and were then used for catalytic gasification of algae at temperature of 300°C. The catalyst increased the oil content at low temperature and the products obtained were bio-oil and biochar to be used as bio-fertilizer. Cobalt oxide and calcium oxide nanoparticles were used due to their reactivity with high surface area which decrease the activation energy and reaction temperature. Bio-oil was transesterified to convert it into biodiesel by using sodium hydroxide catalyst and methanol. These results were confirmed through using various techniques like Fourier infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), gas chromatography–mass spectrometry (GCMS), and particle-induced X-ray emission (PIXE). Results not only confirmed the successful production of oil but also indicated that the nano-catalyst showed good efficiency and increased the oil content at a relatively lower temperature. [ABSTRACT FROM AUTHOR]

A N'-N'-di-n-hexyl-thiodiglycolamide and 2,2'-[(2-ethylhexyl)imino]bis[N,N-bis(2-ethylhexyl)acetamide] impregnated porous silica-based adsorbent was prepared for enhancing the adsorption of palladium ions from simulated high-level liquid waste. The adsorbent exhibited a relatively fast palladium response and selectivity without the use of additional modification reagents. Palladium ions were adsorbed over a wide nitric acid range of 0.6−5 M and a broad temperature range of 288−323 K. The uniform distribution of adsorbed palldium ions onto the study adsorbent was confirmed by PIXE. Successful recovery of more than 90% of the palladium ions was achieved using 0.1 M thiourea via separation by column experiments. Based on the obtained data, it is expected that the prepared adsorbent can be used for the practical separation of palladium ions from high-level liquid waste. [ABSTRACT FROM AUTHOR]

Determining the sequence of inks in a questioned document is important in forensic science. Conventional and micro beam‐based ion beam analysis using Rutherford backscattering spectrometry (RBS) and particle‐induced X‐ray emission were employed to study the depth distribution of chemical elements in plain paper and inks/toner deposited by different pens as well as inkjet and laser printers. Composition depth profiling with high lateral resolution was performed with focus on areas where two different coloring agents overlapped. We identify under which conditions the sequence of inks deposited can be reconstructed, analyzing the continuity of characteristic contributions to the obtained signals, with a focus on the depth‐resolved RBS data. The order of deposition was correctly determined for combinations of two different laser printers and in certain cases for pens. Results indicate a potential for analysis, depending on the composition of staining agent, that is, in particular if heavy species are present in sufficiently high concentration. In such cases, also characters obscured or modified by an agent of different composition can be revealed. Changing the probing depth by modifying the beam energy could yield additional information. [ABSTRACT FROM AUTHOR]

Nowadays the forgery of cultural heritage is on the rise, damaging the patrimony and its cultural value. Objects of value may still be unveiled at various construction sites or by other digging actions. Such objects will always raise questions about their authenticity because they were not unveiled by experts. Such findings will need to be analysed in order to establish their authenticity. The present study is aimed at establishing the authenticity of a small monetary treasury unveiled by archaeological looting in Garvăn, Tulcea, Romania. The treasury was later confiscated from the looters by the Romanian authorities, and in order to eliminate questions about the pieces' authenticity, studies involving characteristic X‐ray emissions and optical microscopy were applied in order to obtain data concerning the treasury's authenticity. [ABSTRACT FROM AUTHOR]

Archived jejunum tissue block specimens from control and simian immunodeficiency virus‐infected rhesus macaques are characterized using particle‐induced X‐ray emission (PIXE) in a MeV ion microprobe with 2 MeV protons. The results show considerable variance in the concentration of some elements (Ti, Mn, and Fe) between viremic and control tissue. Ti, Mn, and Fe are present at levels 50‐fold lower in samples from viremic versus control monkeys, a difference markedly higher than previously reported for infections. Pb and Ti are observed particularly in the crypts of both viremic and control jejunum samples. This is likely to be caused by ingestion of paint fragments picked from the cages used to house the animals. [ABSTRACT FROM AUTHOR]

The self-consistent Ion Beam Analysis (IBA) of cultural heritage samples using the external beam is technically demanding. We report on the calibration of an analysis of glass samples from the Rosslyn Chapel where the interest will ultimately be in the full characterisation of the weathered glass. Such an analysis requires a comprehensive Total-IBA approach using p-PIGE and He-PIXE to obtain "bulk" and surface Na, with H-PIXE/EBS for multielemental depth profiling to 10 μm and He-PIXE/EBS for higher depth resolution near the surface; also with two PIXE detectors as usual for the high and low energy parts of the spectrum. A revised NDF v.10 code capable of a self-consistent handling of all these signals at state-of-the-art accuracy is described, together with the calibration protocols required for such an analysis. Other capabilities of the NDF code not previously discussed are also reviewed. [ABSTRACT FROM AUTHOR]

"Total-IBA" implies the synergistic use of multiple IBA techniques. It has been claimed that Total–IBA inherits the accuracy of the most accurate IBA technique used. A specific example is now given of this where (in vacuo) EBS/PIXE of a glass sample uniform in depth is validated against absolutely calibrated EPMA of the same sample. The EPMA results had a mass closure gap of 2.0 ± 0.6 wt%; the full PIXE analysis determined the composition of this missing 2 wt%. The PIXE calibration was against a single certified glass sample, with uncertainties per line ~10%. Benchmarking also demonstrates ~10% underestimation of the Si scattering cross-section at proton energies ~3 MeV. But the Total-IBA determination of the silica content had a low standard uncertainty of about 2%. This is due to the strong constraints of both the chemical prior and also the mass closure properties of the EBS. Irradiation-induced sodium migration in this soda-lime glass is explored. [ABSTRACT FROM AUTHOR]

This work presents results of macro, micro, and nanoscale surface characterization for a set of Roman denarii, ranging from 136 BCE to 240 CE, using large-scale X-ray fluorescence (XRF) mapping, particle-induced X-ray emission (PIXE) spectroscopy, focused-ion-beam-assisted scanning electron microscopy (FIB-SEM) with energy dispersive spectroscopy (EDS). The combination of XRF and PIXE, with varying beam energies, allowed for visualization and quantification of individual elements as a function of the surface distribution. These results helped to select suitable areas for FIB-SEM-EDS analysis. The edges of selected coins were polished to image the inner composition and surface morphology of the coins using a backscattering electron (BSE) imaging method and EDS mapping. Nanosized lamellas extracted from the coins were investigated by transmission electron microscopy (TEM) as well. The combination of these methods enabled the surface, the subsurface, and volume composition of these coins to be probed to better understand their production methods, their surface treatment methods, and their corrosion. The results also provide evidence that a particular surface treatment method, amalgam silvering, had been used to make authentic Roman coins as early as the third century CE. Unlabelled Image • Evolution of surface manipulation techniques for Roman silver coins studied • X-ray based methods help to visualize the elemental surface distribution of coins. • The high-resolution electron microscopy allows probing coins' surface composition. • Amalgam silvering was used to make authentic coins as early as the third century CE. [ABSTRACT FROM AUTHOR]

The aim of the present study was to measure changes in the serum concentrations of some elements in endotoxin-challenged calves using a particle-induced X-ray emission analysis and to screen for elements useful as diagnostic markers. The results obtained revealed that serum Zn concentrations were more accurate diagnostic markers for detecting endotoxin shock in calves than other elements. Serum Zn level in endotoxin-challenged calve was significantly lower from 8 to 12 hr after the endotoxin challenge than pre-challenge values. In addition, serum Zn concentrations in calves from 4 to 24 hr after endotoxin challenges were significantly lower than those of control. Our results indicate that serum Zn concentration has potential as diagnostic markers for detecting inflammation in calves with endotoxin shock. [ABSTRACT FROM AUTHOR]

Semiconductor detectors for PIXE applications were fabricated using TlBr crystals. The TlBr detectors had a multiple-electrode detector design to minimize the pulse-height loss due to hole trapping. Electrodes containing thallium metal were employed for the TlBr detectors to suppress the polarization phenomena. Energy resolutions of 2.4, 3.3, and 3.8 keV FWHM for 5.9, 22.1, and 59.5 keV photons, respectively, were obtained for a TlBr detector operating at −50 °C. [ABSTRACT FROM AUTHOR]

In the proposed work, an investigation on hazard assessment by lead element and natural radioactivity in cosmetic samples collected from various countries is presented. These samples were face powder, eyebrow paint and henna. The lead element in cosmetic samples was determined using particle-induced X-ray emission. Maximum natural radioactivity concentrations of 226Ra and 40K were found in khol and make-up cosmetic samples, respectively. The qualitative analysis of cosmetic samples showed that lead is the most toxic element found in eyebrow paint samples.

This study conducted an evaluation of elemental composition of concrete in an old nuclear reactor facility using the particle-induced X-ray emission (PIXE) technique. Given that the physical volume of the concrete is huge, easy, and quick analysis of many samples via the PIXE method can expedite the decommissioning work. The result of this study confirmed that it is possible to use the PIXE method for detecting light and medium-heavy elements (from Na to Fe) in concrete without the complicated chemical treatment. Some of these elements contain parent nuclides of Na-24, Al-28, and Fe-55, which are dominant components with residual radioactivity for a period of up to 10 years after facility shutdown. [ABSTRACT FROM AUTHOR]

Aim: To study the biopersistence of a silicon carbide (SiC) nanoaerosol in rat lungs, as time-dependent clearance and spatial distribution. Materials & methods: Sprague-Dawley rats were exposed 6 h/day during 5 days to a SiC nanoaerosol at 4.91 mg SiC/l. SiC biopersistence in rat lungs sections was assessed over 28 days by micro-particle-induced x-ray emission (μPIXE) as 2D maps and by particle-induced x-ray emission (PIXE) for whole-lung quantification. 2D maps were analyzed for SiC spatial distribution as skewness and kurtosis. Results: Half-time clearance was 10.9 ± 0.9 days, agreeing with PIXE measurements. Spatial-temporal analysis of SiC indicated decreased symmetry and homogeneity. Conclusion: Fast SiC clearance points that current nanoaerosol exposure may not be enough to trigger lung overload. Spatial distribution shows an asymmetric and nonhomogeneous SiC clearance. [ABSTRACT FROM AUTHOR]

The increasing use of nanoparticles (NP) in commercial products requires elaborated techniques to detect NP in the tissue of exposed organisms. However, due to the low amount of material, the detection and exact localization of NP within tissue sections is demanding. In this respect, Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) and Ion Beam Microscopy (IBM) are promising techniques, because they both offer sub-micron lateral resolutions along with high sensitivities. Here, we compare the performance of the non-material-consumptive IBM and material-consumptive ToF-SIMS for the detection of ZrO2 NP (primary size 9-10 nm) in rat lung tissue. Unfixed or methanol-fixed air-dried cryo-sections were subjected to IBM using proton beam scanning or to three-dimensional ToF-SIMS (3D ToF-SIMS) using either oxygen or argon gas cluster ion beams for complete sample sputtering. Some sample sites were analyzed first by IBM and subsequently by 3D ToF-SIMS, to compare results from exactly the same site. Both techniques revealed that ZrO2 NP particles occurred mostly agglomerated in phagocytic cells with only small quantities being associated to the lung epithelium, with Zr, S, and P colocalized within the same biological structures. However, while IBM provided quantitative information on element distribution, 3D ToF-SIMS delivered a higher lateral resolution and a lower limit of detection under these conditions. We, therefore, conclude that 3D ToF-SIMS, although not yet a quantitative technique, is a highly valuable tool for the detection of NP in biological tissue. [ABSTRACT FROM AUTHOR]

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.

The increasing use of nanoparticles (NP) in commercial products requires elaborated techniques to detect NP in the tissue of exposed organisms. However, due to the low amount of material, the detection and exact localization of NP within tissue sections is demanding. In this respect, Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) and Ion Beam Microscopy (IBM) are promising techniques, because they both offer sub-micron lateral resolutions along with high sensitivities. Here, we compare the performance of the non-material-consumptive IBM and material-consumptive ToF-SIMS for the detection of ZrO2 NP (primary size 9–10 nm) in rat lung tissue. Unfixed or methanol-fixed air-dried cryo-sections were subjected to IBM using proton beam scanning or to three-dimensional ToF-SIMS (3D ToF-SIMS) using either oxygen or argon gas cluster ion beams for complete sample sputtering. Some sample sites were analyzed first by IBM and subsequently by 3D ToF-SIMS, to compare results from exactly the same site. Both techniques revealed that ZrO2 NP particles occurred mostly agglomerated in phagocytic cells with only small quantities being associated to the lung epithelium, with Zr, S, and P colocalized within the same biological structures. However, while IBM provided quantitative information on element distribution, 3D ToF-SIMS delivered a higher lateral resolution and a lower limit of detection under these conditions. We, therefore, conclude that 3D ToF-SIMS, although not yet a quantitative technique, is a highly valuable tool for the detection of NP in biological tissue.

In the present paper, a Cuban clinoptilolite-type zeolite was used as lead sorbent. The effect of chemical conditioning with 1 mol L NaCl, NaOH and NH solutions at room temperature on the ion exchange capacity for lead uptake by clinoptilolite has been investigated. According to the batch experiments, NH-treated clinoptilolite exhibited the highest sorption capacity. For this material, the effect that contact time, solid-to-liquid ratio and pH have on the removal of lead from aqueous solutions was comprehensively analyzed, and the most suitable values for these parameters were selected afterward. The pseudo-second-order kinetic model was appropriate for the description of the kinetic performance of the sorption. The Langmuir and Freundlich isotherm models were applied to describe sorption process, and the best fit was reached by using the Freundlich model. The nondestructive techniques, namely particle-induced X-ray emission and X-ray fluorescence, have successfully been evaluated for determining lead concentration in water by its concentration in zeolite. In addition, the more traditional flame atomic absorption spectrometry determination of lead in water was also improved. [ABSTRACT FROM AUTHOR]