PIXE Analysis Research Articles

Comparison of in-vacuum micro-PIXE and in-air micro-PIXE for unfixed plant sample

PIXE analysis is very useful for the simultaneous determination of various elements. Typically, when micro-PIXE analysis of biological samples with high water content is performed in a vacuum, freeze-drying methods are used to fix the structure and remove any ice crystals present in a controlled manner to prevent changes or redistribution of elemental content in the sample. This method is essential for cell size analysis. However, we considered that fixation is not always necessary for macroscopic analysis of plant tissue size. Therefore, we investigated the extent to which elemental density changes with vacuum extraction from elemental density ratios obtained from micro-PIXE analysis of Arabidopsis thaliana leaves in-air and in-vacuum. The deformation caused by beam irradiation and the quantitative changes of C, O, and H in the samples were also evaluated by STIM and RBS analyses of Arabidopsis thaliana petal.

Characterization of mineral composition using PIXE and EXAFS analyses to elucidate the Barium adsorption mechanism

Ningyo-toge is a uranium (U) mine that was operative in Japan. Currently, the mining area retains a dump of mill tailings. Groundwater is contaminated with U ore, and mill tailings might contain radioactive elements, such as U and radium (Ra), which can negatively impact the human body. This study determined the soil composition at the tailings dumping site using particle-induced X-ray emission, scanning electron microscopy, and X-ray diffraction and observed the adsorption structure of barium (Ba), an analog of Ra, using X-ray absorption fine structure analysis. The results revealed the existence of silicate minerals, such as quartz and mica, and metal oxides, such as Fe and Mn, in the soil. Ningyo-toge soil is similar to montmorillonite and bentonite. In particular, it was proposed that the adsorption of Ba on Mn oxide is an inner-sphere complex that immobilizes Ba. These findings will provide valuable information for estimating the behavior of Ra in the environment. The results of this study will be helpful for safety assessment and evaluating the impacts on the surrounding environment.

Non-invasive analyze of boron and lithium in 18th century Chinese porcelain enamel and glaze: A PIXE/PIGE study

In enamelling technology, the natural (raw) materials used before the middle of the 19th century combine by nature different elements whose role in the process can be important even in small quantities. Some of these elements – particularly boron, lithium – are difficult to measure non-invasively and are therefore rarely analyzed. Boron and lithium, often used as additional flux in glazes, were quantified by PIXE and PIGE analysis with the extracted beam of the New AGLAE facility in 18th century porcelains samples, French soft-paste from the Manufacture royale de Sèvres and Chinese hard-paste from the reign of the Qing dynasty. The results were compared to previous conclusions made using SEM/EDS and pXRF in order to assert the presence of boron, previously suspected by Raman microspectroscopy, and to detect the presence of lithium, both provided by a particular flux (borax), mentioned in the historical French and Chinese enamel recipes.

Enhanced photocatalytic degradation and synergistic effects of Tin-Doped zinc oxide nanoparticles for environmental remediation

Using zinc acetate and sodium hydroxide as starting reagents, zinc oxide nanoparticles (NPs) were constructed using a co-precipitation process. Various metal elements were incorporated into the nanocomposites. The synthesized samples underwent calcination at different temperatures for a duration of 2 h. Characterization of the samples was conducted employing XRD, SEM, EDS, and PIXE analysis. SEM imagery revealed diverse morphological alterations of ZnO after doping. The whole width at half the maximum of the XRD peaks, which indicates sizes in the nano range, was used to calculate the average crystallite sizes of the samples using Debye-Scherer’s formula. EDS analysis confirmed the production of highly pure ZnO nanostructures via this method. The synthesized bimetallic and tri-metallic NPs were utilized for the degradation of hazardous organic dyes, with the degradation process monitored using UV–visible spectroscopy. This study underscores the significance of doped ZnO NPs as effective agents for biodegradation.

Characterisation of urban aerosol size distribution by radiocarbon and PIXE analyses in a middle-European urban environment for source identification: a pilot study

This study, conducted in Debrecen, Hungary, aimed to analyse atmospheric particulate matter (APM or PM) through radiocarbon and PIXE analyses during the winter smog (23–25 January) and spring (15–18 May) seasons. The information presented in this pilot study aims to provide insight into the importance of utilising detailed characteristics of the mass size distributions of fossil carbon (ff) and contemporary carbon (fC) content. Additionally, it seeks to compare these characteristics with the size distributions of various elements to enable even more accurate PM source identification. In winter, APM concentrations were 86.27 μg/m3 (total), 17.07 μg/m3 (fC) and 10.4 μg/m3 (ff). In spring, these values changed to 29.5 μg/m3, 2.64 μg/m3 and 7.01 μg/m3, respectively. Notably, differences in mass size distribution patterns were observed between the two seasons, suggesting varied sources for contemporary carbon. Biomass burning emerged as a crucial source during the smog period, supported by similar MMAD (Mass Median Aerodynamic Diameter) values and a strong correlation (r = 0.95, p < 0.01) between potassium and fC. In spring, a significant change in the concentration and distribution of fC occurred, with a broad, coarse mode and a less prominent accumulation mode. Ff was found to have similar distributions as PM, with nearly the same MMADs, during both periods. Finally, a comprehensive comparison of modal characteristics identified specific sources for the various components, including biomass burning, vehicle exhaust, coal and oil combustion, vehicle non-exhaust, road dust, tyre abrasion, mineral dust and biogenic emission. This study showcases how using radiocarbon and PIXE analysis in size distribution data can enhance our understanding of the sources of PM and their effects on different size fractions of PM.

PIXE Analysis for Elemental Composition and Concentrations of Tantalite Samples from Oke-Ogun, Oyo State, Nigeria

The elemental composition and concentrations of heavy metals in solid mineral may be a reflection of their economic value and their effects on the environment. Tantalite samples from Oke-Ogun were subjected to elemental analysis using Particle Induced X-ray Emission (PIXE) technique. Twelve samples of tantalite ore [(Fe, Mn) Ta2O6], were obtained from the mining sites. 500 mg of the pulverized samples were pelletized for their elemental composition and concentrations using the PIXE technique. The total number of elements found in the selected (Komu, Eluku, Gbedu and Sepenteri) falls within the range of 16 ̶ 27 elements. Na, Mg, Si, S, K, Ca, Ti, Cr, Mn, Fe, Ni, Zn, As, Sr, Zr, Nb, Ta, W, Bi, Pb. V, P, Mo, Hf, Al, and Rb were reported for the study. Harmful elements like Pb, Cr, As, Zn and Sr were found in samples from the sites with concentrations in the range of (240 ̶ 3000) ppm which is greater than the limits specified by the abundance elements in average crustal rock (2 ̶ 311) ppm. The range of tantalite concentrations in all the sites falls within the range of (111,000 ̶ 370,000) ppm and comparing the range with tantalite samples from other nations reveals that the tantalite from the selected sites are more enriched in tantalite content and by inference will be more of economic values than those from compared nations.

Sarcoma cell-specific radiation sensitization by titanate scrolled nanosheets: insights from physicochemical analysis and transcriptomic profiling

This study aimed to explore the potential of metal oxides such as Titanate Scrolled Nanosheets (TNs) in improving the radiosensitivity of sarcoma cell lines. Enhancing the response of cancer cells to radiation therapy is crucial, and one promising approach involves utilizing metal oxide nanoparticles. We focused on the impact of exposing two human sarcoma cell lines to both TNs and ionizing radiation (IR). Our research was prompted by previous in vitro toxicity assessments, revealing a correlation between TNs' toxicity and alterations in intracellular calcium homeostasis. A hydrothermal process using titanium dioxide powder in an alkaline solution produced the TNs. Our study quantified the intracellular content of TNs and analyzed their impact on radiation-induced responses. This assessment encompassed PIXE analysis, cell proliferation, and transcriptomic analysis. We observed that sarcoma cells internalized TNs, causing alterations in intracellular calcium homeostasis. We also found that irradiation influence intracellular calcium levels. Transcriptomic analysis revealed marked disparities in the gene expression patterns between the two sarcoma cell lines, suggesting a potential cell-line-dependent nano-sensitization to IR. These results significantly advance our comprehension of the interplay between TNs, IR, and cancer cells, promising potential enhancement of radiation therapy efficiency.

Wintertime investigation of PM10 concentrations, sources, and relationship with different meteorological parameters

Meteorological factors play a crucial role in affecting air quality in the urban environment. Peshawar is the capital city of the Khyber Pakhtunkhwa province in Pakistan and is a pollution hotspot. Sources of PM10 and the influence of meteorological factors on PM10 in this megacity have yet to be studied. The current study aims to investigate PM10 mass concentration levels and composition, identify PM10 sources, and quantify links between PM10 and various meteorological parameters like temperature, relative humidity (RH), wind speed (WS), and rainfall (RF) during the winter months from December 2017 to February 2018. PM10 mass concentrations vary from 180 – 1071 µg m−3, with a mean value of 586 ± 217 µg m−3. The highest concentration is observed in December, followed by January and February. The average values of the mass concentration of carbonaceous species (i.e., total carbon, organic carbon, and elemental carbon) are 102.41, 91.56, and 6.72 μgm−3, respectively. Water-soluble ions adhere to the following concentration order: Ca2+ > Na+ > K+ > NH4+ > Mg2+. Twenty-four elements (Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Co, Zn, Ga, Ge, As, Se, Kr, Ag, Pb, Cu, and Cd) are detected in the current study by PIXE analysis. Five sources based on Positive Matrix Factorization (PMF) modeling include industrial emissions, soil and re-suspended dust, household combustion, metallurgic industries, and vehicular emission. A positive relationship of PM10 with temperature and relative humidity is observed (r = 0.46 and r = 0.56, respectively). A negative correlation of PM10 is recorded with WS (r = − 0.27) and RF (r = − 0.46). This study’s results motivate routine air quality monitoring owing to the high levels of pollution in this region. For this purpose, the establishment of air monitoring stations is highly suggested for both PM and meteorology. Air quality standards and legislation need to be revised and implemented. Moreover, the development of effective control strategies for air pollution is highly suggested.

The earliest glass from the territory of Slovenia

This paper presents the results of the analyses of three glass beads from three Bronze Age sites, Medvode-Svetje, Trata near Škofja Loka and Kamna Gorica near Ljubljana. All three sites belong to the Oloris-Podsmreka horizon, which covers the Middle and the beginning of the Late Bronze Age (c. second half of the 16th/first half of the 15th century to 12th century BC). The PIXE and PIGE analyses revealed that only two of the examined beads belong to the Bronze Age. The bead from the Medvode-Svetje site is similar to LMHK beads and is most likely an import from the Frattesina production centre in northern Italy, while the bead from the Trata site has similarities with the eastern Mediterranean or even Mesopotamian area HMg glass. The natron glass bead from Kamna Gorica is probably an Iron Age infiltrate in a Bronze Age layer.

Comparison of analogue and digital silicon drift detectors in PIXE analysis

The AXAS-A silicon drift detector that has been a part of the University of Guelph PIXE system for over a decade has recently been replaced by an AXAS-D unit. The calibration process previously performed on the AXAS-A, which uses a suite of high purity, “thick-target” single element and simple compound standards, was repeated for the AXAS-D. This allows for comparison between the analogue and digital approach to measuring PIXE spectra. The similarities between the results of the two detectors and the high accuracy found in geological applications affirm the validity of the use of an energy-dependent calibration factor within the GUPIX software. The upgrade to a digital detector offers multiple advantages. Unlike the AXAS-A, the AXAS-D contains a pre-amplifier and digital pulse processing circuitry and therefore requires significantly less supporting equipment. The improved count rate of the AXAS-D decreases the time required to complete projects.

PIXE analysis of contaminants in tree rings in proximity of the aluminum processing factory in Ladomerská Vieska (Slovakia)

The aluminum smelter in the Žiar nad Hronom region of central Slovakia was a substantial source of pollution in the past. Five trees were sampled in close proximity to the smelter and the tree rings were chemically processed and analyzed with the PIXE technique. Elevated concentrations of Mg, Al, Si, P, S, K, Ca, Fe, and Zn were observed in tree rings, however, they did not show a significant correlation with PM, HF and SO2 emission rates. Concentration trends show a significant effect of the heartwood-sapwood boundary layer, where a substantial drop or increase was observed between tree-ring sections.

PIXE and pXRF Comparison Analysis of a Mockup Canvas Painting

For the purposes of comparison among different equipments and laboratories involved in atomic-nuclear methodologies applied in arts and archaeometry, a special mockup canvas painting was made with dozens of pigments of different colors and varnishes of different types and manufacturers. This study evaluate two different XRF equipment and PIXE methods as complementary tools to examine canvas paintings. Twenty-four inorganic substances of this mockup canvas were measured in three different laboratories, LEC, LFNA, and LAMFI for the identification of the key elements. In this paper, net count ratios and standard percentage deviations between lines are shown, as well as examples of sensibility to low-content elements that can be used for distinguishing pigments, and a comparison of the penetration of these techniques. The results show the differences between the pXRF and PIXE methodologies and between the two pXRF geometry/equipments employed.

Exactly how free? Constrained choices and product ranges of medieval copper-alloy objects found between the Meuse and Loire rivers (9th–16th centuries CE)

This contribution synthesises the PIXE and ICP-AES elemental analyses carried out on a large dataset, comprising of 300 copper-alloy objects dating mainly to the Late Middle Ages. The objects are drawn from heritage institutions and archaeological contexts in various regions between the Meuse and the Loire rivers (France and Belgium). This investigation focuses on the main elements that make up the alloys (Cu, Zn, Sn, Pb). Past studies have often defined the composition of an alloy as an intentional choice, however in this paper we aim to identify the constraints in alloy manufacture in a bid to understand the degree of freedom enjoyed by craftsmen during this period. We will also evaluate to what degree the constraints imposed by technique, economic conditions and social requirement, affected production in a complex multifactorial system. We have opted to define alloys by object type, functional area and social context, by chronology and product ranges. For cast table- and the kitchenware, we have observed that alloys and the objects are standardised on a trans-regional scale. Conversely, the hammered objects are produced with a greater freedom, leading to a new hypothesis regarding specific workshop practices. Finally, we will propose a predictive model for cast objects that we hope is better suited for the study of heritage objects, their materials and their production processes, to be verified in future studies. This approach emphasises the importance of considering everything that makes an object what it is: its function, status and place in the market, when researching heritage materials.

XANTHO – A simple basic program for fitting X-ray spectra

A code XANTHO for fitting X-ray spectra induced by photons or charge particles was developed as a Lazarus application. Background subtraction is performed by iterative filtering (brushing) of the source spectrum, based on the adapted Kolmogorov-Zurbenko approach. For comparison, a code with top-hat filtering was also developed. Critical comparison was made for a glass standard at PIXE analysis. XANTHO is intended for accurate fitting of individual spectra during analytical work and for sequential fitting at mapping experiments.

External PIXE analysis of a handwritten Persian endowment deed belonging to the Timurid dynasty

The external PIXE analysis yielded valuable information on the constituent elements of the paper, inks, and illumination of a handwritten document belonging to the Timurid dynasty (1485 A.D). The inks were found to be different in terms of their constituent matrix and trace elements. The applied inks are classified into three groups according to their relative concentration of Ca and Fe. The characteristic elements of the pigments suggested their origin. The chemical interaction of the green pigment, which influences the degradation of the paper, is discussed. The results aid the conservator in making treatment decisions. Moreover, the presented data allows the assignment of the provenance and a probable dating of similar samples via the chronology of the used pigments.

X-ray production cross sections induced by 0.8–1.6 MeV/amu 56Fe ions in collision with selected elements from aluminum to bismuth

The K X-ray productions for the Mg, Al, Ti, Cr, Cu, Zn, Zr, Nb, Mo, Ag, Cd, In, Sn, Sb thin films, the L X-ray productions for the Zr, Nb, Mo, Ag, Cd, In, Sn, Sb, Ta, W, Pb, Bi targets and the M X-ray productions for the Ta, W, Pb, and Bi films were investigated using 44.8 MeV, 56 MeV, 67.2 MeV, 78.4 MeV and 89.6 MeV 56Feq+ accelerated beams. The obtained experimental data were compared with the PWBA and ECPSSR theoretical values calculated with the ISICS11 code. A sharp increase in the cross sections for the target elements close to iron is observed. In this way, the X-ray production cross section for the selected chemical element in the PIXE analysis can be maximized with the irradiation mode selection – the energy and species of the incident ion.

Cold Plasma as a Competent Approach to Treat Solid Fiber of Ichnocarpus frutescens: PIXE, XRD, Raman, FT-IR, and SEM Analysis

Cold Plasma as a Competent Approach to Treat Solid Fiber of Ichnocarpus frutescens: PIXE, XRD, Raman, FT-IR, and SEM Analysis

L-shell x-ray production cross sections in 50Sn by 100 keV–300 keV protons

The L-shell x-ray emission of 50Sn has been investigated for the impact of proton with energies from 100 keV to 300 keV. The experimental cross section of individual Lι, Lα, Lβ, Lγ and total L x rays were obtained from the yield. This is significant for the enrichment of existing database and PIXE analysis in applications. The results were compared with the data available in literature, as well as to the theoretical estimations of BEA, PWBA, ECPSSR and ECUSAR using various atomic parameters and considering correction of multiple ionization. The influences of the modification of united atom approximation, the multi-ionized atomic parameters and the selection of different databases on the theory calculation were discussed. On the whole, the experimental data can be well predicted by ECUSAR-MI calculation with Puri et al. and Campbell's atomic parameters.

Improving the accuracy of alpha particle induced X-ray emission analysis: The role of multiple ionization K X-ray satellites

Wavelength-dispersive X-ray spectrometry is used to examine the influence of multiple ionization satellites induced by 3–5 MeV energy helium ion beams upon the accuracy of particle-induced X-ray emission analysis (PIXE). The work extends our prior study of elements magnesium, aluminum and silicon and their oxides to elements phosphorus, chlorine, potassium, calcium, titanium and chromium and, for the latter two, their oxides. Fitting of the spectra with Voigtian peaks enables construction of a database that comprises the mean energies and the relative intensities of up to four distinct satellite groupings. This database provides an empirical means for inclusion of one peak per satellite group when modelling energy-dispersive spectra. This is a useful step towards improving the accuracy of PIXE analysis of materials using helium beams; an example of this is provided using a spectrum recorded by the Curiosity rover on Mars.

Proton beam irradiation induces invisible modifications under the surface of painted parchment

Ion beam analysis plays an important role in cultural heritage (CH) studies as it offers a combination of simultaneous and complementary analytical techniques (PIXE/PIGE/RBS) and spatially resolved mapping functions. Despite being considered non-destructive, the potential risk of beam-induced modifications during analysis is increasingly discussed. This work focuses on the impact of proton beams on parchment, present in our CH in form of unique historical manuscripts. Parchment is one of the organic, protein-based CH materials believed to be the most susceptible to radiation-induced changes. Various modification patterns, observed on parchment cross-sections by optical and electron microscopy are reported: discoloration (yellowing), formation of cavities and denaturation of collagen fibers. Considerable modifications were detected up to 100 µm deep into the sample for beam fluences of 4 µC/cm2 and higher. The presence of ultramarine paint on the parchment surface appears to increase the harmful effects of proton radiation. Based on our results, a maximum radiation dose of 0.5 µC/cm2 can be considered as ‘safe boundary’ for 2.3 MeV PIXE analysis of parchment under the applied conditions.