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The nondestructive investigation of millimeter-sized meteoritic materials is often hindered by self-absorption effects. Using X-ray-based analytical methods, the information depth for many elements (Z < 30) is in the range of up to only a few hundred micrometers, and for low-Z elements (Z < 20), this is reduced even further to only a few tens of micrometers. However, the investigation of these low-Z elements, in particular calcium, aluminum, and magnesium, is of great importance to planetary geologists and cosmochemists, as these elements are regularly used to characterize and identify specific features of interest in extraterrestrial materials, especially primitive chondritic material. In this work, nonresonant inelastic X-ray scattering from core electrons was performed at beamline ID20 of the ESRF in a direct tomography approach in order to visualize these low-Z elements within the millimeter-sized meteoritic samples. The obtained 3D elemental distribution volumes were compared to results from X-ray fluorescence-CT and absorption CT experiments and were found to be in good agreement. Additionally, several regions of interest could be identified within the inelastic scattering volumes, containing information that is not available through the other presented means. As such, the proposed approach presents a valuable tool for the nondestructive investigation of low-Z elemental distributions within millimeter-sized extraterrestrial materials, such as the samples of the Hayabusa2 sample return mission.

Selenium (Se) is an essential trace element for humans and animals with a narrow window between deficiency and toxicity levels. Application of conventional chemical Se fertilizers to increase the Se content of crops in Se deficient areas could result in environmental contamination due to the fast leaching of inorganic Se. Slow-release Se-enriched biofertilizers produced from wastewater treatment may therefore be beneficial. In this study, the potential of Se-enriched biomaterials (sludge and duckweed) as slow-release Se biofertilizers was evaluated through pot experiments with and without planted green beans (Phaseolus vulgaris). The Se concentration in the bean tissues was 1.1–3.1 times higher when soils were amended with Se-enriched sludge as compared to Se-enriched duckweed. The results proved that the Se released from Se-enriched biomaterials was efficiently transformed to health-beneficial selenoamino acids (e.g., Se-methionine, 76–89%) after being taken up by beans. The Se-enriched sludge, containing mainly elemental Se, is considered as the preferred slow-release Se biofertilizer and an effective Se source to produce Se-enriched crops for Se-deficient populations, as shown by the higher Se bioavailability and lower organic carbon content. This study could offer a theoretical reference to choose an environmental-friendly and sustainable alternative to conventional mineral Se fertilizers for biofortification, avoiding the problem of Se losses by leaching from chemical Se fertilizers while recovering resources from wastewater. This could contribute to the driver for a future circular economy. This work has been financially supported by the Special Research Fund (BOF, BOFCHN2017000801) from Ghent University as well as the Chinese Scholarship Council (CSC, 201606300023). P.T. wishes to acknowledge the FWO for his personal funding (FWO, 12Q7718 N). The authors acknowledge Ana María Murillo Abril for her assistance with the lab work, as well as the DUBBLE staff, FWO and NWO for their support during synchrotron experiments at ESRF. Ivet Ferrer is grateful to the Government of Catalonia (Consolidated Research Group 2017 SGR 1029) Peer Reviewed Objectius de Desenvolupament Sostenible::6 - Aigua Neta i Sanejament Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables

In the 1960s, a solid-hilted sword dating to the second half of the Middle Bronze Age (1450–1300 BC) was dredged up in a gravel quarry in the Rhône river at the village of Champagneux (Savoie, France). The sword belongs to the octagonal-hilted swords (German: Achtkantschwerter). This type, mainly found in the northern Alpine region and southern Scandinavia, was until then unknown in France. X-ray fluorescence (XRF) analyses and high-resolution X-ray computed tomography (μCT) of the hilt were carried out to understand how the hilt was cast and fixed to the blade. Thanks to the opportunities offered by these techniques, we were able to reconstruct the chaîne opératoire of this sword with a close inspection of the internal structure of the hilt. Furthermore, we visualised the surface of the sword’s tang located inside the hilt, which shows a series of five vertically arranged marks. Until now, similar symbols were only known on Late Bronze Age bracelets and tools, predominantly in the eastern part of the Alpine region. Although their exact function remains enigmatic, these marks are believed to be markers left by craftsmen on the object during their manufacture. On the solid-hilted sword from Champagneux, these marks could be linked to a way for the craftsman to remember which blade and hilt were supposed to be joined together, shedding light on the organisation of the production process behind this kind of weapon. Dans les années 1960, une épée à poignée métallique datant de la seconde moitié du Bronze moyen (1450–1300 av. J.-C.) fut draguée dans une gravière du Rhône à Champagneux (Savoie). Il s’agit d’une épée à fusée octogonale (en allemand : Achtkantschwert). Ce type, caractéristique de la région nord-Alpine et du sud de la Scandinavie, était jusqu’alors inconnu en France. Des analyses par spectroscopie de fluorescence X (XRF) et tomographie haute résolution par rayons X (μCT) ont été réalisées afin de comprendre comment la poignée a été coulée puis fixée à la lame. Ces méthodes nous ont ainsi permis de reconstituer la chaîne opératoire de cette épée en réalisant une inspection minutieuse de la structure interne de sa poignée. Nous avons par ailleurs été en mesure de visualiser la surface de la languette de la lame, insérée à l’intérieur du manche, qui présente une série de cinq marques disposées verticalement. Des éléments similaires n’étaient jusqu’à présent connus uniquement sur des outils et parures de du Bronze final, essentiellement dans la partie orientale de l’arc alpin. Bien que leur fonction exacte demeure inconnue, ces marques pourraient être des marqueurs laissés sur les objets au moment de leur fabrication. Dans le cas de l’épée de Champagneux, il pourrait s’agir d’un moyen pour l’artisan d’identifier rapidement dans son atelier la lame et la poignée devant être assemblées. Ces marques nous permettent ainsi d’obtenir de nouvelles informations l’organisation de la production de ce type d’arme.

This chapter focuses on the basic principles of X-ray fluorescence (XRF) and micro-XRF imaging applicable to cultural heritage research, presenting basic figures of merit and application examples based on the use of advanced laboratory and synchrotron radiation sources. Related methods of analysis making use of absorption edge phenomena by X-ray absorption spectroscopy, including X-ray absorption near-edge structure and extended X-ray absorption fine structure spectroscopy will also be discussed.

Cultural Heritage objects are frequently unavailable for transportation to laboratory facilities due to their size, location or local Cultural Heritage preservation regulations. The development of handheld XRF (hXRF) systems has, therefore, proven to be essential in the study of unmovable objects. In this study, two handheld XRF instruments—Bruker™ Tracer III SD® and Olympus™ Innov-X Delta Premium—were compared and evaluated using tesserae from the Mosaico de los Amores (Linares, Spain). Given their portability, the user-friendly nature of their operating systems and their overall performance, both hXRF instruments are highly recommended for in situ campaigns in Cultural Heritage studies. However, the detection limits calculated for each element point towards a better detection of low-Z elements when using the two-beam mode of the Olympus™ Innov-X Delta Premium hXRF. This study underlines the importance of systems that allow the analysis of the same point with analytical conditions optimized for different chemical elements.

Clathrin-mediated endocytosis (CME) is the gatekeeper of the plasma membrane. In contrast to animals and yeasts, CME in plants depends on the TPLATE complex (TPC), an evolutionary ancient adaptor complex. The mechanistic contribution of the individual TPC subunits to plant CME remains however elusive. In this study, we used a multidisciplinary approach to elucidate the structural and functional roles of the evolutionary conserved N-terminal Eps15 homology (EH) domains of the TPC subunit AtEH1/Pan1. By integrating high-resolution structural information obtained by X-ray crystallography and NMR spectroscopy with all-atom molecular dynamics simulations, we provide structural insight into the function of both EH domains. Whereas one EH domain binds negatively charged PI(4,5)P2lipids, unbiased peptidome profiling by mass-spectrometry revealed that the other EH domain interacts with the double N-terminal NPF motif of a novel TPC interactor, the integral membrane protein Secretory Carrier Membrane Protein 5 (SCAMP5). Furthermore, we show that AtEH/Pan1 proteins control the internalization of SCAMP5 via this double NPF peptide interaction motif. Collectively, our structural and functional studies reveal distinct but complementary roles of the EH domains of AtEH/Pan1 have in plant CME and connect the internalization of SCAMP5 to the TPLATE complex.

Besides conventional scanning X-ray fluorescence imaging at synchrotron sources, full-field X-ray fluorescence (FF-XRF) imaging techniques that do not implicitly require spatial scanning of the sample have become available. FF-XRF has become achievable thanks to the development of a new type of energy dispersive CCD-based 2D detector, also referred to as a ‘color X-ray camera (CXC)’ or ‘SLcam’. We report on different imaging schemes for biological samples using FF-XRF imaging: (a) 2D ‘zoom’ imaging with pinhole optics using the ‘camera obscura’ principle; (b) 2D ‘fixed magnification’ imaging using magnifying polycapillary optics; and (c) 3D-FF-XRF imaging using an X-ray sheet beam or computed tomography (CT). The different FF-XRF imaging modes are illustrated using the crustacean Daphnia magna, a model organism for investigating the effects of metals on organism/ecosystem health, and foraminifera, a class of amoeboid protist. Detailed analytical characterization of the set-up is performed through analyzing various reference materials in order to determine limits of detection (LODs) and sensitivities. Experiments were performed using the BAMline at the BESSY synchrotron (Berlin, Germany) and using the P06 Hard X-ray Microprobe at the PETRAIII synchrotron (Hamburg, Germany).

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.

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Analytical chemistry 92(1), 1106-1113 (2020). doi:10.1021/acs.analchem.9b04176, Detection of rare earth elements (REE) is commonly performed with destructive techniques such as (LA)-ICPMS or coupled to a destructive sample preparation. When investigating unique geological samples, such as cometary, asteroidal, or interstellar material from sample return missions or inclusions in deep Earth diamonds, a nondestructive method is preferred. The presented nondestructive highly sensitive wavelength-dispersive X-ray fluorescence spectroscopy (WD-XRF) technique is designed to measure the L-lines of REE between 4.5 and 7 keV with a sensitivity down to the ppm level. REE fluorescence L-lines are often only separated by a few eV from neighboring XRF-lines and cannot be resolved by an energy dispersive approach especially in the presence of transition metal K-lines. In our spectrometer the characteristic X-rays emitted by the sample are dispersed by a fixed Ge(111) analyzer crystal over the active area of an energy dispersive pn-charge-coupled-device (pnCCD) detector, enabling high energy resolution detection of X-rays differentiated by their corresponding Bragg angles. The use of an energy-dispersive 2D detector enables the simultaneous acquiring of XRF-lines while eliminating any ambiguities due to potential contribution from higher order diffraction effects or other diffraction planes and thereby increases the sensitivity by reducing the (scatter) background. This detection method shows an energy resolution of 12 eV for the Ti–Kα fluorescence line and has a sensitivity down to 0.50 ppm for REE L-lines. The method was optimized specifically for the nondestructive analysis of inclusions in deep Earth diamonds, yielding in situ quantitative information about up-to-now inaccessible elemental (REE) composition patterns together with the more abundant transition metals like Ti, Cr, Mn, and Fe. This information is of great importance to decipher the role that deep Earth plays in the global carbon and fluid cycle., Published by American Chemical Society, Columbus, Ohio

Synergistic catalysis holds great promise to enhance the catalytic performance of heterogeneous catalysts suffering from sluggish reaction kinetics. Much effort has been dedicated to the development of bimetallic systems in which the two promoter elements display synergistic benefits compared to monometallic counterparts. However, the use of bimetallic catalysts inescapably raises the cost of preparation and environmental issues. This study discovers a synergistic effect when using a bipyridine covalent triazine framework (bipy-CTF) as support for an IrIII complex in the aerobic oxidation reaction. The detailed mechanistic study provides insights into the function of the bipy-CTF in this synergistic catalysis. The EPR and in-situ XANES analyses confirm the applicability of bipy-CTF to activate oxygen and alcohol, resulting in an enhancement of the performance of the IrIII complex to exceed the activity of the homogeneous counterpart. This is an unprecedented report on promoting the activity of a heterogeneous catalyst through its solid support.

Die herkommliche Bestimmung der Kristallvorzugsorientierung (kristallographische Textur) beruht auf Rontgenbeugung mit Flachendetektoren und 2D-Daten. Echte, ortsaufgeloste 3D-Informationen erfordern eine Probendrehung im Strahl. Dabei wird das beleuchtete Volumen standig verandert und das Streusignal verschmiert, was die Bestimmung komplexer Strukturen verhindert. Diese Einschrankung lasst sich mit energieauflosender Laue-Beugung umgehen. Es wurde eine Methode entwickelt, um einen grosen Teil des reziproken Raums abzudecken und aus der Energie der Rontgenphotonen die dritte Raumdimension zu errechnen. Das Verfahren wurde auf Kohlenstofffasern und Hummerpanzer, als Beispiel fur biomineralisiertes Gewebe, angewendet. Das besondere Potenzial dieser Methode liegt darin, dass sie nur eine einzige Messung erfordert, sowie am direkten Erfassen von 3D-Informationen ohne Vorwissen uber die Probe. Das Verfahren ermoglicht daher das Abrastern groser Proben mit komplexer Struktur und eroffnet die konzeptuelle Moglichkeit, Texturanderungen in situ zu verfolgen, z. B. wahrend Kristallisationsvorgangen.

Polycapillary optics, consisting of bundles of narrow hollow glass channels, are regularly used in the field of (micro-)X-ray fluorescence (XRF) spectroscopy to focus X-rays down to a microscopic spot while increasing the flux density of the beam on the sample. Polycapillaries guide X-ray photons through multiple total reflection events, similar to how light is guided within optic fibers. Although the use of polycapillaries in XRF spectroscopy allows for fairly straightforward qualitative elemental analysis, fundamental parameter (FP) based quantification remains difficult due to the energy dependent photon transmission efficiency, focal size, acceptance, etc. of these optics. In order to predict the polycapillary and input beam parameter dependent beam forming properties, a multithreaded Monte Carlo based polycapillary X-ray ray tracing code is presented. Apart from supporting photon ray tracing in ‘ideal’ straight, conical and ellipsoidal shaped polycapillary optics, it also allows for the simulation of photon propagation through arbitrarily shaped optics to account for small deviations from the ideal shape, as is often the case in real world examples. The current code allows for the simulation of so-called ‘leak events’, where the probability of a photon traveling through a capillary wall is taken into account, and also includes support for photon beam polarization effects. The simulated results show good agreement with experimental results obtained at the BM26A beamline of the European Synchrotron Radiation Facility (ESRF, Grenoble, France). The (poly)capillary X-ray ray tracing simulation code, called ‘polycap’, developed in the C language and with bindings for Python, is released under the GPLv3 license. The code is expected to assist in the quantification of (poly)capillary based X-ray fluorescence spectroscopy and may yield additional insight into the manufacturing and development of polycapillary optics.

At the French synchrotron facility SOLEIL, a new X-ray imaging facility PUMA (Photons Utilisés pour les Matériaux Anciens) has been made available to scientific communities studying materials from cultural heritage. This new instrument aims to achieve 2D and 3D imaging with microscopic resolution, applying different analytical techniques including X-ray fluorescence spectroscopy (XRF), X-ray absorption spectroscopy (XAS), X-ray diffraction and phase-contrast imaging. In order to discover its capabilities a detailed analytical characterization of this beamline as an analytical and imaging tool is deemed necessary. In this work, (confocal) XRF and XAS analyses are demonstrated using the Seymchan pallasite meteorite and an Antarctic unmelted micrometeorite as case studies. The obtained spatial resolution (2 µm × 3 µm) and sensitivity (detection limits

Writing on paper is essential to civilization, as Pliny the Elder remarks in his Natural History, when he describes the various types of papyri, the method of manufacturing them, and all that concerns writing materials in the mid-first century AD. For this reason, a rigorous scientific study of writing is of fundamental importance for the historical understanding of ancient societies. We show that metallic ink was used several centuries earlier than previously thought. In particular, we found strong evidence that lead was intentionally used in the ink of Herculaneum papyri and discuss the possible existence of ruled lines traced on the papyrus texture. In addition, the metallic concentrations found in these fragments deliver important information in view of optimizing future computed tomography (CT) experiments on still-unrolled Herculaneum scrolls to improve the readability of texts in the only surviving ancient Greco-Roman library.

It is crucial to understand the structural origins of macroscopic properties in silicate glasses for their high-tech applications. An example of such an application is chemically strengthened boroaluminosilicate glasses that are exposed to an ion exchange process during which alkali ions (e.g. Na+) are replaced by larger (e.g. K+) ions. Despite the empirically thorough understanding of this exchange process, much less is known about the fundamental physics of the process. Since Fe atoms are a suitable probe for monitoring chemical stress-induced changes in the local structure in the chemically strengthened glasses, a set of chemically strengthened boroaluminosilicate glasses containing 1 mol% Fe2O3 are here studied using depth-resolved confocal X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy. Information on the Fe oxidation state, coordination number, and bond distance as a function of the sample depth and glass composition is obtained. These new insights on chemical stress-induced changes will aid in the further development and improvement of such damage-resistant glasses.

The functionalization of titania based materials with noble metal cocatalysts such as gold or platinum is a well known procedure to improve the catalytic activity of these materials in for example the degradation of organic pollutants or CO conversion. Parameters such as cocatalyst load, noble metal particle size and oxidation state influence the efficiency of these materials. We have impregnated a mesoporous titania powder with a gold salt and used different synthesis routes to reduce the gold ions. A structural analysis was performed using electron microscopy and nitrogen sorption. An X-ray absorption near edge structure spectroscopy study, in both high and low resolution, was performed to investigate the influence of the different reduction methods on the oxidation state of the gold atoms. This technique can also provide information on the local environment of the gold atoms and their interaction with the titanium dioxide host. We found that varying the reduction method has a significant impact on the oxidation state of the gold cocatalysts. This lead to varying interactions with the titania support and charging of the gold nanoparticles.

A new, commercially available, mobile system combining X-ray diffraction and X-ray fluorescence has been evaluated which enables both elemental analysis and phase identification simultaneously. The instrument makes use of a copper or molybdenum based miniature X-ray tube and a silicon-Pin diode energy-dispersive detector to count the photons originating from the samples. The X-ray tube and detector are both mounted on an X-ray diffraction protractor in a Bragg-Brentano theta:theta geometry. The mobile instrument is one of the lightest and most compact instruments of its kind (3.5 kg) and it is thus very useful for in situ purposes such as the direct (non-destructive) analysis of cultural heritage objects which need to be analyzed on site without any displacement. The supplied software allows both the operation of the instrument for data collection and in-depth data analysis using the International Centre for Diffraction Data database. This paper focuses on the characterization of the instrument, combined with a case study on pigment identification and an illustrative example for the analysis of lead alloyed printing letters. The results show that this commercially available light-weight instrument is able to identify the main crystalline phases non-destructively, present in a variety of samples, with a high degree of flexibility regarding sample size and position. (C) 2015 Elsevier B.V. All rights reserved.

Complexes of Cu(ii) with triethanolamine (TEA) are widely used in aqueous precursor solutions of Cu-based catalysts and metal oxides such as YBa2Cu3O7-δ superconductors. An outstanding question is whether such complexes are multinuclear in solution. Here, we use various spectroscopic techniques to unmistakably prove the existence of such multimers. Firstly, we introduce an original approach based on NMR spectroscopy and the Evans method that establishes the existence of multimers in aqueous solution at pH 4 and higher, and allows precise monitoring of the formation of these complexes with increasing pH. Secondly, we use extended X-ray absorption fine structure (EXAFS) spectroscopy to show that a Cu-Cu interaction exists at pH 9.5, which is not observed in acidic (pH 2) solutions. Finally, NMRD measurements reveal additional structural information regarding the multinuclear complexes. Knowledge concerning the nature of Cu(ii)-TEA complexes in solution is of great relevance in view of the design of speciation models to predict the stability of copper triethanolamine-based precursor solutions.

A novel plug-and-play setup based on polycapillary X-ray optics enables three-dimensional (3D) confocal X-ray fluorescence (XRF) and X-ray absorption spectroscopy down to 8 × 8 × 11 μm3 (17 keV) at the European Synchrotron Radiation Facility Collaborative Research Group Dutch–Belgian Beamline, BM26A. A complete description and analytical characterization is presented, together with two recently performed experimental cases. In Deep Earth diamond Sao Luiz-Frankfurt am Main 16, an olivine-rich inclusion was mapped with full 3D XRF elemental imaging. The preliminary tests on Iron Gall ink contained in an historical document, a letter from the court of King Philip II of Spain, reveal both the delicate nature of Iron Gall ink and the lack of Fe–Ni chemical bonding.

X-ray diffraction (XRD) and electron paramagnetic resonance spectroscopy (EPR) were combined to study the structural transformations induced by temperature, pressure and air humidity of the "breathing" metal-organic framework (MOF) MIL-53(Al), doped with paramagnetic V

A new three-dimensional (3D) micro X-ray fluorescence (μXRF) methodology based on a novel 2D energy dispersive CCD detector has been developed and evaluated at the P06 beamline of the Petra-III storage ring (DESY) in Hamburg, Germany. This method is based on the illumination of the investigated sample cross-section by a horizontally focused beam (vertical sheet beam) while fluorescent X-rays are detected perpendicularly to the sheet beam by a 2D energy dispersive (ED) CCD detector allowing the collection of 2D cross-sectional elemental images of a certain depth within the sample, limited only by signal self-absorption effects. 3D elemental information is obtained by a linear scan of the sample in the horizontal direction across the vertically oriented sheet beam and combining the detected cross-sectional images into a 3D elemental distribution data set. Results of the 3D μXRF analysis of mineral inclusions in natural deep Earth diamonds are presented to illustrate this new methodology.

X-ray absorption near-edge structure (XANES) spectroscopy is a well-known nondestructive technique that allows for chemical state and local structure determination. Spatially resolved oxidation state imaging is possible performing full-field transmission mode XANES experiments, providing chemical state information on the illuminated sample area, but these experiments are limited to thin, concentrated samples. Here we present the use of a unique energy dispersive (ED) pnCCD detector, the SLcam, for full-field fluorescence mode XANES experiments, thereby significantly relaxing the constraints on sample thickness. Using this new detection methodology, spatially resolved chemical state information on millimeter-sized sample areas can be obtained with microscopic resolution in moderate measuring times (less than 15 h), obtaining a XANES profile for each of nearly 70,000 points in a single measurement without the need of scanning the sample through the beam. Besides a description of the use of this detector for micro-XANES applications, we also present the proof of concept for fluorescence mode micro-XANES using a Fe(0)/Fe2O3 model sample and a Nitisol soil sample, which was measured to obtain iron chemical state distribution information.

X-ray diffraction (XRD) and electron paramagnetic resonance spectroscopy (EPR) were combined to study the structural transformations induced by temperature, pressure and air humidity of the breathing metalorganic framework (MOF) MIL-53(Al), doped with paramagnetic VIV ions, after activation. The correlation between in situ XRD and thermogravimetric analysis measurements showed that upon heating this MOF in air, starting from ambient temperature and pressure, the narrow pore framework first dehydrates and after that makes the transition to a large pore state (lp). The EPR spectra of VIV[double bond, length as m-dash]O molecular ions, replacing AlOH in the structure, also allow to distinguish the as synthesized, hydrated (np-h) and dehydrated narrow pore (np-d), and lp states of MIL-53(Al). A careful analysis of EPR spectra recorded at microwave frequencies between 9.5 and 275 GHz demonstrates that all VIV[double bond, length as m-dash]O in the np-d and lp states are equivalent, whereas in the np-h state (at least two) slightly different VIV[double bond, length as m-dash]O sites exist. Moreover, the lp MIL-53(Al) framework is accessible to oxygen, leading to a notable broadening of the VIV[double bond, length as m-dash]O EPR spectrum at pressures of a few mbar, while such effect is absent for the np-h and np-d states for pressures up to 1 bar.

Analytical chemistry 89(3), 2123 - 2130 (2017). doi:10.1021/acs.analchem.6b04828, Using X-ray absorption near edge structure (XANES) spectroscopy, information on the local chemical structure and oxidation state of an element of interest can be acquired. Conventionally, this information can be obtained in a spatially resolved manner by scanning a sample through a focused X-ray beam. Recently, full-field methods have been developed to obtain direct 2D chemical state information by imaging a large sample area. These methods are usually in transmission mode, thus restricting the use to thin and transmitting samples. Here, a fluorescence method is displayed using an energy-dispersive pnCCD detector, the SLcam, characterized by measurement times far superior to what is generally applicable. Additionally, this method operates in confocal mode, thus providing direct 3D spatially resolved chemical state information from a selected subvolume of a sample, without the need of rotating a sample. The method is applied to two samples: a gold-supported magnesia catalyst (Au/MgO) and a natural diamond containing Fe-rich inclusions. Both samples provide XANES spectra that can be overlapped with reference XANES spectra, allowing this method to be used for fingerprinting and linear combination analysis of known XANES reference compounds., Published by American Chemical Society, Columbus, Ohio

Technological developments such as atmospheric plasma jets for industry can be adapted for the conservation of cultural heritage. This application might offer a potential method for the removal or transformation of the corrosion on historical photographs. We focus on daguerreotypes and present an in-depth study of the induced changes by a multi-analytical approach using optical microscopy, scanning electron microscopy, different types of transmission electron microscopy and X-ray absorption fine structure. The H2-He afterglow removes S from an Ag2S or Cu2S layer which results in a nano-layer of metallic Ag or Cu on top of the deteriorated microstructure. In case the corrosion layer is composed of Cu-Ag-S compounds, our proposed setup can be used to partially remove the corrosion. These alterations of the corrosion results in an improvement in the readability of the photographic image.

A new sulfone functionalized vanadium metal-organic framework (MOF), denoted as SO2-COMOC-2, has been synthesized solvothermally. Its structural and gas sorption properties towards CO2 and CH4 have been evaluated and compared to those of the pristine COMOC-2 material. The SO2-COMOC-2 shows a remarkable increase in CO2 capacity at ambient pressure (2.13 mmol g(-1) at 273 K vs. 1.23 mmol g(-1) for the pristine COMOC-2). Additionally, the high pressure CO2 sorption isotherm shows a distinctive two-step sorption behavior with a final capacity of 12.45 mmol g(-1) for SO2-COMOC-2 at 303 K, while for CH4 a typical Type I isotherm was obtained with a capacity of 4.13 mmol g(-1). In situ synchrotron X-ray powder diffraction measurements have been carried out to characterize the structural flexibility of the materials, showing both the presence of large pore and narrow pore form. Furthermore, synchrotron XANES and a variety of spectroscopic techniques have been utilized to verify the presence of hydroxyl groups and the existence of the mixed vanadium oxidation states in the titled MOF structure.

Conventional analysis of the preferred orientation of crystallites (crystallographic texture) involves X-ray diffraction with area detectors and 2D data output. True 3D, spatially resolved information requires sample rotation in the beam, thus changing the probed volume, which introduces signal smearing and precludes the scanning of complex structures. This obstacle has been overcome by energy-dispersive Laue diffraction. A method has been devised to reach a large portion of reciprocal space and translate the X-ray photon energy into the missing third dimension of space. Carbon fibers and lobster exoskeleton as examples of biomineralized tissue have been analyzed. The major potential of this method lies in its "one-shot" nature and the direct 3D information requiring no previous knowledge of the sample. It allows the texture of large samples with complex substructures to be scanned and opens up the conceptual possibility of following texture changes in situ, for example, during crystallization.

The writing in carbonized Herculaneum scrolls, covered and preserved by the pyroclastic events of the Vesuvius in 79 AD, was recently revealed using X-ray phase-contrast tomography, without the need of unrolling the sensitive scrolls. Unfortunately, some of the text is difficult to read due to the interference of the papyrus fibers crossing the written text vertically and horizontally. Recently, lead was found as an elemental constituent in the writing, rendering the text more clearly readable when monitoring the lead X-ray fluorescence signal. Here, several hypotheses are postulated for the origin and state of lead in the papyrus writing. Multi-scale X-ray fluorescence micro-imaging, Monte Carlo quantification and X-ray absorption microspectroscopy experiments are used to provide additional information on the ink composition, in an attempt to determine the origin of the lead in the Herculaneum scrolls and validate the postulated hypotheses.

Many historical silver objects are composed of sterling silver, a silver alloy containing small amounts of copper. Besides the dramatic impact of copper on the corrosion process, the chemical composition of the corrosion layer evolves continuously. The evolution of the surface during the exposure to a Na2S solution was monitored by means of visual observation at macroscopic level, chemical analysis at microscopic level and analysis at the nanoscopic level. The corrosion process starts with the preferential oxidation of copper, forming mixtures of oxides and sulphides while voids are being created beneath the corrosion layer. Only at a later stage, the silver below the corrosion layer is consumed. This results in the formation of jalpaite and at a later stage of acanthite. The acanthite is found inside the corrosion layer at the boundaries of jalpaite grains and as individual grains between the jalpaite grains but also as a thin film on top of the corrosion layer. The corrosion process could be described as a sequence of 5 subsequent surface states with transitions between these states.

After internal contamination, uranium rapidly distributes in the body; up to 20 % of the initial dose is retained in the skeleton, where it remains for years. Several studies suggest that uranium has a deleterious effect on the bone cell system, but little is known regarding the mechanisms leading to accumulation of uranium in bone tissue. We have performed synchrotron radiation-based micro-X-ray fluorescence (SR μ-XRF) studies to assess the initial distribution of uranium within cortical and trabecular bones in contaminated rats' femurs at the micrometer scale. This sensitive technique with high spatial resolution is the only method available that can be successfully applied, given the small amount of uranium in bone tissue. Uranium was found preferentially located in calcifying zones in exposed rats and rapidly accumulates in the endosteal and periosteal area of femoral metaphyses, in calcifying cartilage and in recently formed bone tissue along trabecular bone. Furthermore, specific localized areas with high accumulation of uranium were observed in regions identified as micro-vessels and on bone trabeculae. These observations are of high importance in the study of the accumulation of uranium in bone tissue, as the generally proposed passive chemical sorption on the surface of the inorganic part (apatite) of bone tissue cannot account for these results. Our study opens original perspectives in the field of exogenous metal bio-mineralization.

Quaternary slope deposits near the Lesse river in the Famenne region, south Belgium, contain scattered rounded rock fragments (5-15 cm diameter) that are typically characterized by a dark coating or patina. This dark surface resembles rock varnish occurrences. To establish the nature of the coatings, chemical, mineralogical and petrographical analyses were performed. The coatings are essentially Fe/Mn oxide features, developed as surface deposits on the rock fragments with associated impregnation of the rock substrate. The Fe/Mn compounds are amorphous or at least poorly crystalline. The coating also shows enrichment in clay minerals compared to the matrix of the covered rock fragments. Some of these characteristics are typical for rock varnish, but the coating does not show a layered structure. We hypothesize that the coating was formed by precipitation of Mn and Fe supplied by water, after burial of the rock fragments in the surrounding slope deposits, and was not affected by atmospheric deposition. Despite its strong macroscopic resemblance to rock varnish the patina on the Famenne rocks must most likely be classified as a heavy-metal skin. In quartaire hellingsafzettingen nabij de Lesse komen afgeronde keien (5-15 cm diameter) voor met een donkere patina aan het oppervlak. De patina doet sterk denken aan woestijnlak. Chemisch, mineralogisch en petrografisch onderzoek toont aan dat de patina voornamelijk bestaat uit een toplaag van Fe/Mn-oxide met gedeeltelijke impregnatie van het gesteente. De Fe/Mn-verbindingen zijn amorf of hoogstens zwak kristallijn. De patina vertoont ook een aanrijking met kleimineralen vergeleken met de steenmatrix rond de keien zelf. Woestijnlak vertoont dezelfde kenmerken, maar de patina op de Famennestenen mist een gelaagde structuur. Het lijkt erop dat de patina gevormd werd door neerslag van door water aangevoerd ijzer en mangaan, en niet door atmosferische neerslag. Ondanks de sterke macroscopische gelijkenis met woestijnlak lijkt het erop dat de patina moet beschouwd worden als een zgn. metal skin: een aanrijking, zonder gelaagde structuur, van metalen op gesteente.

High resolution X-ray radiography and computed tomography are excellent techniques for non-destructive characterization of an object under investigation at a spatial resolution in the micrometer range. However, as the image contrast depends on both chemical composition and material density, no chemical information is obtained from this data. Furthermore, lab-based measurements are affected by the polychromatic X-ray beam, which results in beam hardening effects. New types of X-ray detectors which provide spectral information on the measured X-ray beam can help to overcome these limitations. In this paper, an energy dispersive CCD detector with high spectral resolution is characterized for use in high resolution radiography and tomography, where a focus is put on the experimental conditions and requirements of both measurement techniques.

Introduction: The Chicxulub meteorite impact is the only recognized impact event on Earth that produced and preserved an ejecta layer still traceable today on a global scale [1]. Therefore, it is possible to directly compare, both texturally and compositionally, the material from the crater in Mexico with its deposits worldwide. This approach provides vital constraints on the dynamic processes within the Chicxulub impact plume and the incorporation of different target lithologies as well as a potential meteoritic component within the ejecta. Well-preserved glassy impact spherules smaller than 1 mm, found at proximal marine Cretaceous-Paleogene (K-Pg) sites around the Gulf of Mexico (Beloc [2] and Arroyo El Mimbral [3]) have shown to exhibit a striking similarity with the Chicxulub in-crater melt sheet in terms of geochemistry and age [4]. Here we describe a K-Pg site from a terrestrial setting ~3050 km from the crater [5], that documents the first occurrence of uniquely preserved Chicxulub microtektites, which are embedded in fossilized amber. In this study, we report the petrography, oxidation state, and major and trace element composition of these glassy impact spherules and compare the results with data from other K-Pg sites to interpret their formational mechanisms and link with the Yucatán target lithologies.

Nanothermometry is a fast-developing field of research due to the need of remote, precise, reliable and non-invasive temperature sensing in real time. This is both important for research, aswell as for industrial applications. However, new nanomaterials suitable for nanothermometry are often difficult to design as the synthesis might be challenging to control, and the fine-tuning of morphology, crystallinity and size is a sophisticated task. Schlenk line based synthesis are a well-known and frequently used route to grow nanoparticles for nanothermometry. However, reports on LaF3 synthesized employing a Schlenk line based thermal decomposition route are very rare. In this presentation we will overview our work carried out on the preparation of nanosized and well-dispersed LaF3 and the influence of different bases, namely LiOH, KOH, NaOH and NaF, used in a thermal decomposition Schlenk line synthesis. It has been reported before that an increase in the respective base and with it the pH value was assumed to accelerate the release of CF3COO- ions.1 Chien et.al linked this to an accelerated growth of LaF3 nanocrystals. Using varied reaction conditions we have worked to optimize the best synthesis route for the development of the nano-sized LaF3.

Metal-modified covalent triazine frameworks (CTFs) have attracted considerable attention in heterogeneous catalysis due to their strong nitrogen-metal interactions exhibiting superior activity, stability and hence recyclability. Herein, we report on a post-metalation of a bipyridine-based CTFs with an Ir(I) complex for C H borylation of aromatic compounds. Physical characterization of the Ir(I)-based bipyCTF catalyst in combination with density functional theory (DFT) calculations exhibit a high stabilization energy of the Ir-bipy moiety in the frameworks in the presence of B2Pin2. By using B2Pin2 as a boron source, Ir(I)@bipyCTF efficiently catalyzed the C H borylation of various aromatic compounds with excellent activity and good recyclability. In addition, XAS analysis of the Ir(I)@bipyCTF gave clear evidence for the coordination environment of the Ir.