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Wavelength dispersive X-ray fluorescence (WD-XRF) spectroscopy is a widely used instrumental spectroscopy method for a variety of samples and it requires no or a minimal of sample preparation. Compared to using the more conventional energy dispersive XRF spectrometers, WD-XRF spectroscopy has the advantage of a highly improved energy resolution, making this technique suitable for the detection of characteristic X-rays separated by only a few eV. WD-XRF is established both in industry for routine analyses and in the academic world for high-end research and development of the method. WD-XRF spectroscopy can be probed with a laboratory X-ray source and if higher X-ray-beam intensities, monochromatic and polarized beams are required a synchrotron X-ray radiation source can be used. In (synchrotron) radiation facilities all over the world interesting new setups are characterized and used. This review paper will give an overview of the important characteristic properties, such as energy resolution, sensitivity, and the reachable energy range of the different types of WD-XRF setups available and reported in the last 20 years, based on laboratory X-ray sources, radiation facility sources or availability as a commercial instrument. The commercially available instruments are listed by the manufacturer and type of instrument, and for each instrument at least one example of an application is shown. [ABSTRACT FROM AUTHOR]

Abstract: Background: A tailored approach to nutrition and physical activity advice can support women following childbirth in managing barriers (i.e. time and childcare) to making healthy lifestyle changes. The aim of the present study was to evaluate the implementation, acceptability and preliminary efficacy of a personally tailored nutrition and exercise programme for postpartum women delivered via video‐consultations by an accredited practising dietitian (APD) and accredited exercise physiologist (AEP). Methods: In this feasibility study (VITAL change for mums), postpartum (3–12 months) women (body mass index ≥25 or >2 kg above pre‐pregnancy weight) who were seeking to achieve a healthy weight participated in a single‐arm intervention. Participants received up to five real‐time personalised video‐consultations (2 × APD, 2 × AEP, 1 × either) over the 8‐week intervention period. Implementation (recruitment, retention, utilisation), acceptability (participant satisfaction) and preliminary efficacy (anthropometry, dietary intake, cardiovascular fitness, physical activity level, psychological wellbeing) were assessed. Results: Thirty women [mean (SD) age 31.6 (3.1) years, body mass index 29.0 (4.0) kg m−2, 100% married/de facto, 80% university level education] were recruited within 10 days and 27 completed the study. Women's mean (SD) ratings (out of a score of 5) indicated satisfaction with the video‐consultations [4.4 (0.9)] and the online setting [4.5 (0.8)]. Women agreed that accessing an APD [4.4 (0.8)] and AEP [4.3 (0.9)] was easier using video‐consultations than attending an in‐person consultation. Statistically significant improvements in waist circumference, body composition, cardiorespiratory fitness, dietary intake and physical activity were observed from baseline to 8 weeks. Conclusions: The findings of the present study suggest that a nutrition and exercise intervention delivered by qualified health professionals via video‐consultations is feasible, acceptable and achieves positive outcomes for women following childbirth. [ABSTRACT FROM AUTHOR]

The study aimed at identifying the stressors experienced by teachers. The research was conducted by applying the survey ''Management standards for work-related stress'', elaborated by Health and Safety Executive (HSE). The qualitative-research results reveal the main risk factors felt and expressed, useful to the managerial feedback, necessary for the improvement of both occupational environment within undergraduate education units, and human-resource management. [ABSTRACT FROM AUTHOR]

Describes the quantitative trace element analysis of individual fly ash particles using X-ray microfluorescence (XRF). Characterization of particulate materials having grainlike structure; Validity of XRF simulation model; Estimation of matrix attenuation.

Apatite is present as an accessory phase in many meteorites and is often formed as a secondary product of aqueous alteration. Its propensity to incorporate rare earth elements (REE) results in apatite usually being the main REE‐bearing phase in hydrously altered meteorites. Asteroid Ryugu is thought to have experienced pervasive aqueous alteration and material collected from the surface of Ryugu is expected to provide insight into asteroidal aqueous alteration processes without influence by terrestrial weathering. Morphologies and mineral associations of apatite grains from five rock fragments collected from the asteroid Ryugu by the Hayabusa2 spacecraft were examined and their REE concentrations were measured by synchrotron X‐ray fluorescence (SXRF) spectroscopy. The main minerals associated with apatite are dolomite, magnetite, and pyrrhotite. Grain boundary corrosion of the interfaces between apatite assemblages and the surrounding matrix suggest that paragenetic formation on the asteroid was followed by a later episode of hydrous alteration. Light REE (LREE) concentration levels recorded at 20–150 times those of bulk CI levels together with a steady increase from LREE toward enrichment of medium REE (MREE, up to Er) at 50–400 times bulk CI levels may suggest postgenetic removal of LREE from Ryugu apatite grains by late‐stage circulation of a hydrothermal fluid. [ABSTRACT FROM AUTHOR]

Interprets capillary generated spatial and angular distributions of x-rays using ray-tracing code for capillary optics. Types of surface imperfections; Examinations of capillaries of various dimensions; Comparisons of simulated and experimental capillary output patterns; Effects of surface roughness and axial distortions.

Reliable identification of chondrules, calcium‐aluminum‐rich inclusions (CAIs), carbonate grains, and Ca‐phosphate grains at depth within untouched, unprepared chondritic samples by a nondestructive analytical method, such as synchrotron X‐ray fluorescence (SXRF) computed tomography (CT), is an essential first step before intrusive analytical and sample preparation methods are performed. The detection of a local Ca‐enrichment could indicate the presence of such a component, all of which contain Ca as major element and/or Ca‐bearing minerals, allowing it to be precisely located at depth within a sample. However, the depth limitation from which Ca‐K fluorescence can travel through a chondrite sample (e.g., ∼115 µm through material of 1.5 g cm−3) to XRF detectors leaves many Ca‐bearing components undetected at deeper depths. In comparison, Sr‐K lines travel much greater distances (∼1700 µm) through the same sample density and are, thus, detected from much greater depths. Here, we demonstrate a clear, positive, and preferential correlation between Ca and Sr and conclude that Sr‐detection can be used as proxy for the presence of Ca (and, thus, Ca‐bearing components) throughout mm‐sized samples of carbonaceous chondritic material. This has valuable implications, especially for sample return missions from carbonaceous C‐type asteroids, such as Ryugu or Bennu. Reliable localization, identification, and targeted analysis by SXRF of Ca‐bearing chondrules, CAIs, and carbonates at depth within untouched, unprepared samples in the initial stages of a multianalysis investigation insures the valuable information they hold of pre‐ and post‐accretion processes in the early solar system is neither corrupted nor destroyed in subsequent processing and analyses. [ABSTRACT FROM AUTHOR]

Developmental vulnerability in children often impacts social, educational, and health outcomes that then determine a child's developmental trajectory into adolescence and adulthood. It is widely accepted that early detection of vulnerability and implementation of targeted educational support can optimise children's outcomes, particularly when implemented via a holistic, cross-institutional approach with community and multi-stakeholder engagement. However, developing and sustaining community collaboration on the scale necessary to achieve such an outcome is challenging, and communities seeking to do so may be able to learn from others where such outcomes have been achieved. It is in this context that we describe the formation and activities of the Griffith University-Nerang Alliance (GU-NA) collaboration, a co-designed community-wide endeavour aimed at ensuring every child has a healthy and successful start to school in Nerang and surrounding suburbs in southeast Queensland, Australia. Using the Knowledge-To-Action Framework, we reflect on the process for establishing and sustaining the collaboration focussing on supporting children's transition to school, including challenges and lessons learned. We highlight the importance of a systematic, co-designed approach to collaboration, and share processes and lessons learned with the view to supporting similar collaborations in other communities. [ABSTRACT FROM AUTHOR]

We studied the working conditions in Early Childhood Education and Care (ECEC). The aim was to explore how ECEC staff experience work demands and resources and how these relate to turnover intentions. The research was based on a modified Job Demands-Resources model (Bakker and Demerouti in J Manage Psychol 22(3):309-328, 2007) according to which job strain is influenced by both job demands and resources. The sample was identified through trade union registers and the data were collected via a survey (N = 538). The findings show a rather high proportion of turnover intentions. Both general workload and emotional workload were related to turnover intentions, and they were mediated by participation. However, leadership satisfaction did not mediate the relationship between workload and turnover intentions. This study contributes to the knowledge on risk factors related to intentions to leave the ECEC profession in the Finnish as well as the international context. It is urgent to know more about factors related to turnover because a high rate undermines trust in the ECEC sector and negatively impacts staff and children. [ABSTRACT FROM AUTHOR]

Abstract: X-ray scattering may contribute significantly to the spectral background of X-ray fluorescence (XRF) spectra. Based on metrological measurements carried out with a scanning electron microscope (SEM) having attached a well characterised X-ray source (polychromatic X-ray tube) and a calibrated energy dispersive X-ray spectrometer (EDS) the accuracy of a physical model for X-ray scattering is systematically evaluated for representative samples. The knowledge of the X-ray spectrometer efficiency, but also of the spectrometer response functions makes it possible to define a physical spectral background of XRF spectra. Background subtraction relying on purely mathematical procedures is state-of-the-art. The results produced by the analytical model are at least as reliable as those obtained by Monte-Carlo simulations, even without considering the very challenging contribution of multiple scattering. Special attention has been paid to Compton broadening. Relevant applications of the implementation of the analytical model presented in this paper are the prediction of the limits of detection for particular cases or the determination of the transmission of X-ray polycapillary lenses. [ABSTRACT FROM AUTHOR]

Abstract: MCSHAPE is a Monte Carlo code for the simulation of gamma and X-ray diffusion in matter which gives a general description of the evolution of the polarisation state of the photons. The model is derived from the so-called ‘vector’ transport equation. The three-dimensional (3D) version of the code can accurately simulate the propagation of photons in heterogeneous media originating from either polarised (i.e. synchrotron) or unpolarised sources, such as X-ray tubes. Photoelectric effect, Rayleigh and Compton scattering, the three most important interaction types for photons in the considered energy range (1–1000keV), are included in the simulation with the state-of-art extent of detail. In this paper, the 3D version of the code MCSHAPE is presented. The sample is described using the so-called voxel model. Results from the validation studies and applications of the code to scanning XRF and XRF tomography experiments are discussed. [Copyright &y& Elsevier]

Microanalytical techniques for elemental composition and nuclide-specific analysis have been used to identify the origin and the leachability of depleted uranium particles. The soil particle samples were collected from Kosovo area a few years after the war, the presence of fine particles with depleted uranium as major component was easily identified by EPMA and SIMS. The ultrafine uranium particles were often attached to larger soil particles and contained Ti and Al, being typical components of the penetrator and its cladding. The oxidation state of uranium in the single particles was measured by micro-XANES and found to be in the less soluble form IV while every particle contained a small fraction of mobile uranium VI as well. [Copyright &y& Elsevier]

• Creation of a chemical fingerprint using Raman and XRF spectroscopy. • Characterization of majolica tile glazes of Belgian wall tiles. • Towards non-destructive discrimination of Belgian tile manufacturers. • Discrimination between brown and white majolica tile glazes. Identifying the manufacturer of historical wall tiles is often based on visual inspection by an expert. This is a subjective and time-consuming approach, as it can only be performed on sight by few experts. In this work, it is evaluated whether Raman and X-ray fluorescence (XRF) spectroscopy can create a chemical fingerprint to discriminate the tile manufacturers based on their provenance. Using both analytical techniques and combining this with chemometrical analysis, different historical Belgian tile manufacturers are characterized. We were successful in discriminating the brown from the white glazes, as well as for discriminating most Belgian tile manufacturers based on their origin. For the latter, only the results of the white glazes were used. The results show that both Raman and XRF parameters are important markers, which is underlining the significance of their combined use and opens perspectives for their non-destructive use to distinguish the tile manufacturers, in situ. [ABSTRACT FROM AUTHOR]

Abstract Microbeam X-ray fluorescence (XRF) spectroscopy is applied, next to an art-historical analysis, to determine the time and place of origin of Chinese blue-and-white porcelain. In the performed experiments, two groups of kraak porcelain samples (A and B) have been analyzed with XRF spectroscopy to obtain quantitative data, (trace) elemental distributions and fingerprints within different regions of interest. The outcome was processed with Principal Component Analysis (PCA), and with the obtained results it was possible to conclude that the two groups show similar elemental fingerprints and were manufactured in the same time period with a comparable use of raw materials. Additionally, X-ray absorption spectroscopy (XAS) measurements have been performed on the pigment layer, confirming the use of Cobalt Blue as an underglaze pigment. Highlights • μXRF analysis of kraak porcelain shows details on manufacturing period and location. • Raw materials of the porcelain body originate from the same region or mining field. • White paint layer in one group is the result of previous restoration after 1920. • The used underglaze pigment is Cobalt Blue. • Seawater has no significant influence on the elemental distribution. [ABSTRACT FROM AUTHOR]

Here, the excellent thermal sensing capability of a multinuclear lanthanide polyoxometalate in the cryogenic region (＜100 K) is presented for the first time. Up till now, no lanthanide polyoxometalates have been studied for their use as ratiometric luminescent thermometers. The investigated Tb3+ polyoxometalate cluster is doped with 1.6% (P1) and 8.4% (P2) of Eu3+ ions. When excited into the Mo–O charge transfer bands, at room temperature only the emission of the Eu3+ ions is observed suggesting a very efficient energy transfer between Mo–O→Tb3+→Eu3+. Only in the cryogenic region the emission of Tb3+ is also witnessed. [ABSTRACT FROM AUTHOR]

A novel quantitative reconstruction model for synchrotron-based confocal X-ray fluorescence imaging has been developed and validated. The theoretical approach uses a new generalized system of equations of the Fundamental Parameter Method (FPM) to calculate the 2D distribution of the concentration values of the trace, minor, and major elements. For the reconstruction procedure of the 2D quantitative μXRF calculations, a serial-type specialised iterative algorithm was developed based on successive approximation of the elementary composition of each individual voxel in the sample. This procedure is capable of neglecting serious numerical difficulty arising at the simultaneous-approaching solution of the huge number of variables involved in the non-linear FPM equations. The model describes the absorption of the primary and secondary X-ray beams in the sample volume and the photoelectric excitation process of characteristic X-ray emission in each sample voxel. For validation of this new evaluation method, standard samples were measured using monoenergetic synchrotron radiation at beamline L in HASYLAB. [ABSTRACT FROM AUTHOR]

In this research, the transparent glaze layers of Chinese porcelain samples were investigated. Depending on the production period, these samples can be divided into two groups: the samples of group A dating from the Kangxi period (1661–1722), and the samples of group B produced under emperor Qianlong (1735–1795). Due to the specific sample preparation method and the small spot size of the X-ray beam, investigation of the transparent glaze layers is enabled. Despite the many existing research papers about glaze investigations of ceramics and/or porcelain ware, this research reveals new insights into the glaze composition and structure of Chinese porcelain samples. In this paper it is demonstrated, using micro-X-ray Fluorescence (μ-XRF) spectrometry, multivariate data analysis and statistical analysis (Hotelling's T-Square test) that the transparent glaze layers of the samples of groups A and B are significantly different (95% confidence level). Calculation of the Seger formulas, enabled classification of the glazes. Combining all the information, the difference in composition of the Chinese porcelain glazes of the Kangxi period and the Qianlong period can be demonstrated. [ABSTRACT FROM AUTHOR]

The trace element content and distribution - including rare Earth elements (REEs) - measured in mm-sized asteroidal samples returned by JAXA's Hayabusa2 mission are important chemical parameters to decipher asteroid Ryugu's chronology of formation linked to early Solar System processes. In order to identify and analyze ancient Solar Nebula components, such as calcium‑aluminum-rich inclusions (CAIs), by their trace element and REE content, a synchrotron beam with an incident energy of 90 keV is used to optimize the XRF signal and increase the information depth in the sample. The application of a (sub-)microscopic X-ray beam with such a high excitation energy not only allows for the detection of a wide range of heavy elements, but also to study their 3-dimensional distribution in mm-sized samples by means of X-ray fluorescence computed tomography (XRF-CT). The experiment was performed in anticipation of the initial analysis of the Hayabusa2 return samples at beamline ID15a of the European Synchrotron Radiation Facility (ESRF), Grenoble, France. The samples were analyzed with a focused beam of 0.5 × 0.5 μm2, achieving limit of detection values as low as 0.5 ppm with an acquisition time of 1 s. Here we present results of scanning XRF(-CT) analysis of a mm-sized sample of the Murchison meteorite, a Mighei type chondrite (CM2), wherein a 9.6 × 11.5 × 8.2 μm3 CAI phase was detected and analyzed. The CAI grain is shown to be detectable throughout the entire sample volume (~700 μm) during an XRF-CT scan over a full 360° angular range, thus proving the applicability of the method to study the microscopic distribution of high-Z elements at trace level concentration within millimeter-sized asteroidal particles. [Display omitted] • Preparation for the initial analysis of Jaxa's Hayabusa2 mission return samples. • Study of the 3D elemental distribution in mm-sized CM2 Murchison meteorite • Detailed analysis of a 9.6 × 11.5 × 8.2 μm3 inclusion with high energy XRF(-CT) • Inclusion is a suggested CAI with a structured core of ultra-refractory elements. • XRF(-CT) is highly suitable to detect phases in unique extra-terrestrial samples. [ABSTRACT FROM AUTHOR]

The ultimate origin of water in the Earth's hydrosphere is in the deep Earth-the mantle. Theory and experiments have shown that although the water storage capacity of olivine-dominated shallow mantle is limited, the Earth's transition zone, at depths between 410 and 660 kilometres, could be a major repository for water, owing to the ability of the higher-pressure polymorphs of olivine-wadsleyite and ringwoodite-to host enough water to comprise up to around 2.5 per cent of their weight. A hydrous transition zone may have a key role in terrestrial magmatism and plate tectonics, yet despite experimental demonstration of the water-bearing capacity of these phases, geophysical probes such as electrical conductivity have provided conflicting results, and the issue of whether the transition zone contains abundant water remains highly controversial. Here we report X-ray diffraction, Raman and infrared spectroscopic data that provide, to our knowledge, the first evidence for the terrestrial occurrence of any higher-pressure polymorph of olivine: we find ringwoodite included in a diamond from Juína, Brazil. The water-rich nature of this inclusion, indicated by infrared absorption, along with the preservation of the ringwoodite, is direct evidence that, at least locally, the transition zone is hydrous, to about 1 weight per cent. The finding also indicates that some kimberlites must have their primary sources in this deep mantle region. [ABSTRACT FROM AUTHOR]

Lake sediments contain valuable information about past volcanic and seismic events that have affected the lake catchment, and they provide unique records of the recurrence interval and magnitude of such events. This study uses a multilake and multiproxy analytical approach to obtain reliable and high-resolution records of past natural catastrophes from ~600-yr-old annually laminated (varved) lake sediment sequences extracted from two lakes, Villarrica and Calafquén, in the volcanically and seismically active Chilean Lake District. Using a combination of micro-X-ray fluorescence (μXRF) scanning, microfacies analysis, grain-size analysis, color analysis, and magnetic-susceptibility measurements, we detect and characterize four different types of event deposits (lacustrine turbidites, tephra-fall layers , runoff cryptotephras, and lahar deposits) and produce a revised eruption record for Villarrica Volcano, which is unprecedented in its continuity and temporal resolution. Glass geochemistry and mineralogy also reveal deposits of eruptions from the more remote Carrán-Los Venados volcanic complex, Quetrupillán Volcano, and the Huanquihue Group in the studied lake sediments. Time-series analysis shows 112 eruptions with a volcanic explosivity index (VEI) 2 from Villarrica Volcano in the last ~600 yr, of which at least 22 also produced lahars. This signifi cantly expands our knowledge of the eruptive frequency of the volcano in this time window, compared to the previously known eruptive history from historical records. The last VEI 2 eruption of Villarrica Volcano occurred in 1991. Based on the last ~500 yr, for which we have a complete record from both lakes, we estimate the probability of the occurrence of future eruptions from Villarrica Volcano and statistically demonstrate that the probability of a 22 yr repose period (anno 2013) without VEI 2 eruptions is 1.7%. This new perspective on the recurrence interval of eruptions and historical lahar activity will help improve volcanic hazard assessments for this rapidly expanding tourist region, and it highlights how lake records can be used to signifi cantly improve historical eruption records in areas that were previously uninhabited. [ABSTRACT FROM AUTHOR]

The unique potential of nanoscale elemental imaging of major/minor and trace-level elemental distributions within thin biological tissue sections of the ecotoxicological model organism Daphnia magna is demonstrated by synchrotron radiation nano-X-ray fluorescence (nano-XRF). The applied highly specialized sample preparation method, coupled with the high spatial resolution (∼180 nm) and high X-ray photon flux (6 × 10 photons/s) available at the European Synchrotron Radiation Facility (ESRF) ID22NI beamline proved to be critical for the high-quality visualization of (trace-)metal distributions on the submicron level within the target structures of interest. These include the branchial sacs on the thoracic appendages (epipodites) of D. magna, which are osmoregulatory regions where ion exchange occurs. For the main element of interest (Zn), detection limits of 0.7 ppm (3 ag) was reached in fast-scanning mode using an acquisition time of 0.3 s/pixel. As demonstrated, synchrotron radiation nano-XRF revealed the elemental distributions of Ca, Fe, and Zn within this osmoregulatory region on the submicron scale, aiding the exploration of possible detoxification mechanisms of Zn within D. magna at the subtissue level. [ABSTRACT FROM AUTHOR]

Partial least squares (PLS) regression-based methods have been proven to be a good alternative for quantification in X-ray fluorescence spectroscopy. These methods are fast and easy to use though giving satisfactory results under certain conditions. One of these conditions is the necessity of having a great number of spectra to build the model (training set). The choice of the constituent concentration range in the training set has a big influence on the accuracy of the model. Better accuracy is obtained if the model is built in relatively narrow regions containing (or close to) the real concentration value. In the present work, Monte Carlo (MC) simulated spectra are used to form the training set. The advantage to use MC generated training spectra is the unlimited availability of perfect standards. This paper aims to improve the accuracy of the method by introducing a multiple step procedure in order to build the PLS model using narrow concentration range close to (or containing) the real concentration values in the samples to be measured. This approach consists of an initial guess of the constituents' concentrations and a preliminary PLS model before building the final model. The prediction of ten MC simulated alloy standard samples containing Ti, Mn, Fe, Co, Cu, Zn, Sr, Zr, and Mo using this method allowed to have average relative prediction errors less than 5% for elements with narrow concentration ranges. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

X-ray fluorescence (XRF) spectroscopy and Raman spectroscopy are preferential analytical techniques to study cultural heritage objects, since both techniques may provide complementary information in a non-destructive manner. Moreover, the application of microscopic beams allows the investigation of heterogeneous samples on the microscopic level and the study of the heterogeneity of particular samples. The micro-XRF method became already a routine analytical imaging method also because of the well-established spectrum evaluation methodology enabling specific data handling procedures. These include multivariate statistical analysis procedures such as principal components analysis (PCA) in order to explore and describe the acquired data, and clustering techniques in order to find similar pixels (or areas) in the obtained images. In the case of the micro-Raman technique, however, the usual approach is to perform a single spot analysis of only a few selected positions in order to ultimately identify the material on the basis of the comparison with Raman spectra obtained from reference materials. However, when samples are heterogeneous, imaging is still to be preferred in order to deal with the problem of sampling. With the arrival of a new micro-Raman spectrometer at the UGent laboratories, there was the need to explore the possibilities of Raman imaging. One of the most important aspects of imaging is the time needed for the analysis. Therefore, the influence of different instrumental parameters, such as resolution (low or high) and measuring time per pixel, on the quality of Raman spectra and images was investigated in order to evaluate the possibility of performing fast Raman mappings because of the need to identify the regions of interest on the art object in a more systematic manner. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that exposure of the freshwater invertebrate Daphnia magna to dietary Zn may selectively affect reproduction without an associated increase of whole body bioaccumulation of Zn. The aim of the current research was therefore to investigate the hypothesis that dietary Zn toxicity is the result of selective accumulation in tissues that are directly involved in reproduction. Since under field conditions simultaneous exposure to both waterborne and dietary Zn is likely to occur, it was also tested if accumulation and toxicity under combined waterborne and dietary Zn exposure is the result of interactive effects. To this purpose, D. magna was exposed during a 16-day reproduction assay to Zn following a 5 × 2 factorial design, comprising five waterborne concentrations (12, 65, 137, 207, and 281 μg Zn/L) and two dietary Zn levels (49.6 and 495.9 μg Zn/g dry wt.). Tissue-specific Zn distribution was quantified by synchrotron radiation based confocal X-ray fluorescence (XRF). It was observed that the occurrence of reproductive inhibition due to increasing waterborne Zn exposure (from 65 μg/L to 281 μg/L) was accompanied by a relative increase of the Zn burdens which was similar in all tissues considered (i.e., the carapax, eggs, thoracic appendages with gills and the cluster comprising gut epithelium, storage cells and ovaries). In contrast, the impairment of reproduction during dietary Zn exposure was accompanied by a clearly discernible Zn accumulation in the eggs only (at 65 μg/L of waterborne Zn). During simultaneous exposure, bioaccumulation and toxicity were the result of interaction, which implies that the tissue-specific bioaccumulation and toxicity following dietary Zn exposure are dependent on the Zn concentration in the water. Our findings emphasize that (i) effects of dietary Zn exposure should preferably not be investigated in isolation from waterborne Zn exposure, and that (ii) XRF enabled us to provide possible links between tissue-specific bioaccumulation and reproductive effects of Zn. [ABSTRACT FROM AUTHOR]

Abstract: The Breviary of Arnold of Egmond is one of the most wealthily illuminated fifteenth century manuscripts in the Northern Netherlands. The manuscript originally contained a number of full-page miniatures, which were all removed at an unknown date before 1902. The three remaining miniatures studied here, are today part of different collections, but they were brought together for an exhibition. Although several historical and art historical details of this breviary have extensively been studied, no examination of the materials used was undertaken before. Analytical techniques, such as mobile Raman spectroscopy, can be used to characterise and identify these materials in a non-invasive way. This paper presents the results of the in situ Raman analysis of three full-page miniatures of the Breviary of Arnold of Egmond. During this study, different pigments could be identified, such as lead white (2PbCO3·Pb(OH)2), lead–tin yellow type I (Pb2SnO4), ultramarine (Na8–10Al6Si6O24S2–4), massicot (PbO), vermilion (HgS) and red lead (Pb3O4). Next to identification of the pigments, visual analysis was used to detect differences and similarities between the stylistic elements of the three analysed folios. [Copyright &y& Elsevier]

Abstract: A selection of illuminations of the 12th century manuscript Liber Floridus was analysed with Raman spectroscopy (in situ and laboratory measurements), X-ray fluorescence spectroscopy, UV-fluorescence photography and infrared reflectography (IRR). The aim of this study is to determine the pigments used, in order to search for anachronisms. Using a combination of Raman spectroscopy (molecular information) and X-ray fluorescence spectroscopy (elemental information) following pigments could be identified: ultramarine (Na8–10Al6Si6O24S2–4), azurite (2CuCO3·Cu(OH)2), caput mortuum (Fe2O3), vermilion (HgS), orpiment (As2S3) and lead white (2PbCO3·Pb(OH)2). Moreover, two synthetic red pigments, PR4 and PR176, and a degradation product, gypsum (CaSO4·2H2O), were present in the manuscript. To establish the origin of the modern materials UV-fluorescence photography was used. Infrared reflectography (IRR) was applied to visualise the underdrawing of the investigated folios. [Copyright &y& Elsevier]

Abstract: A systematic series of measurements has been carried out with monochromatic X-ray excitation with synchrotron radiation in order to check a physical model on X-ray scattering. The model has recently been successfully tested for the case of polychromatic, unpolarised excitation emitted by an X-ray tube. Our main purpose is the modelling of a physical background in X-ray fluorescence spectra, so that improved quantitative results can be achieved especially for strongly scattering specimens. The model includes single Rayleigh and Compton scattering in the specimen, the effect of bound electrons, the challenging Compton broadening and the polarisation degree. Representative specimens, measurement geometries and excitation energies have been selected with synchrotron monochromatic light at BAMline/BESSY II. Monte-Carlo simulations have been also carried out in order to evaluate the quality of the results achieved with the model. [Copyright &y& Elsevier]

The article discusses developments and applications of three-dimensional elemental imaging by means of synchroton radiation micro X-ray fluorescence (micro-XRF) in environmental chemistry. Synchrotron radiation (SR) sources within electron or positron storage rings have been the most brilliant sources of hard X-rays available for scientists today. It also tackles elemental imaging in environmental toxicology.

The hard x-ray microprobe beamline, ESRF-ID22, is primarily devoted to x-ray fluorescence spectroscopy. New requirements in terms of detection limits and acquisition rates fostered the installation and commissioning of a new Gresham multielement Si(Li) detector. It is based on a concentric and oriented array of 13 Si(Li) crystals viewing the same emission point. Beyond the energy resolution, linearity tests, and measurements of detection limits, the influence of the geometrical arrangement of the 13 elements has been investigated. In particular, the relationship between the scattering contribution to the fluorescence spectra and the angular position of individual Si(Li) crystals has been assessed. After optimization, the acquisition time can be reduced by a factor of 10 compared to what can be achieved with a single-element Si(Li) detector. [ABSTRACT FROM AUTHOR]

A Monte Carlo code for the simulation of X-ray imaging and spectroscopy experiments in heterogeneous samples is presented. The energy spectrum, polarization and profile of the incident beam can be defined so that X-ray tube systems as well as synchrotron sources can be simulated. The sample is modeled as a 3D regular grid. The chemical composition and density is given at each point of the grid. Photoelectric absorption, fluorescent emission, elastic and inelastic scattering are included in the simulation. The core of the simulation is a fast routine for the calculation of the path lengths of the photon trajectory intersections with the grid voxels. The voxel representation is particularly useful for samples that cannot be well described by a small set of polyhedra. This is the case of most naturally occurring samples. In such cases, voxel-based simulations are much less expensive in terms of computational cost than simulations on a polygonal representation. The efficient scheme used for calculating the path lengths in the voxels and the use of variance reduction techniques make the code suitable for the detailed simulation of complex experiments on generic samples in a relatively short time. Examples of applications to X-ray imaging and spectroscopy experiments are discussed. [Copyright &y& Elsevier]

A combined micro-PIXE and micro-SRXRF method has been used for the characterization of impact materials collected at the well-known Barringer Meteor Crater. Elemental maps were recorded and concentrations were determined by micro-PIXE method for the major constituents of samples. Micro-SRXRF technique was used for the complementary measurement of medium and high atomic number elements, especially the siderophilic ones. Altogether, approximately 40 elements were analyzed. These results elucidate many steps of the formation mechanism of the various impact-metamorphosed objects. [Copyright &y& Elsevier]

A compact, light weight and relatively inexpensive μ-XRF instrument that allows for non-destructive and local analysis of sub-mm samples with minor/trace level sensitivity was developed. Two versions of this prototype instrument exist: a table-top version that can be used in a laboratory environment while for in situ measurements a readily transportable version was constructed. Polycapillary lenses are used to focus the primary X-ray beam down to the level of 70–100 μm in diameter. Relative detection limits of transition elements in biological and glass matrices are situated at the 10–100 ppm level. These instruments are useful for characterization of various materials from the cultural heritage and forensic sector. [Copyright &y& Elsevier]

Based on nanofocusing refractive x-ray lenses a hard x-ray scanning microscope is currently being developed and is being implemented at beamline ID13 of the European Synchrotron Radiation Facility (Grenoble, France). It can be operated in transmission, fluorescence, and diffraction mode. Tomographic scanning allows one to determine the inner structure of a specimen. In this device, a monochromatic (E=21 keV) hard x-ray nanobeam with a lateral extension of 47×55 nm2 was generated. Further reduction of the beam size to below 20 nm is targeted. [ABSTRACT FROM AUTHOR]