TY - JOUR A1 - Sennikov, P. A1 - Ermakov, A. A1 - Kornev, R. A1 - Gornushkin, Igor B. T1 - Laser induced dielectric breakdown in reactive mixture SiF4 + H2 N2 - Important chemical process of reduction of SiF4 by hydrogen is realized in laser induced dielectric breakdown (LIDB) plasma in a gas mixture of SiF4 and H2. The process may be an alternative to a method of Plasma enhanced chemical vapor deposition (PECVD) which is commonly used for production of pure and isotopically pure silicon films. The composition of laser induced plasma in gases SiF4, SiF4 + H2, SiF4 + H2 + Ar at atmospheric pressure is studied and compared to the composition of inductively coupled plasma (ICP) in the same gases but at reduced pressure of 3 Torr. The gaseous products of chemical reactions are inferred from optical emission spectroscopy (OES) and IR spectroscopy. The reaction products of silicon fluoride SiF and fluorosilanes SiHxFy (x, y = 1, 2, 3) in LIDB plasma are observed and confirmed by equilibrium chemistry calculations and simulations of plasma expansion dynamics using a fluid dynamic-chemical plasma model. It is further suggested that chemisorption of fluorinated species like SiFx (x = 1, 2) followed by the surface reaction with H-atoms lead to a formation of silicon-to‑silicon bonds on a substrate surface. A conclusion is drawn that energetic laser induced plasma can prove efficient for one-step PECVD by hydrogen reduction of SiF4. KW - Silicon halides KW - Chemical vapor deposition KW - Laser induced dielectric breakdown KW - Hydrogen reduction PY - 2021 DO - https://doi.org/10.1016/j.sab.2021.106099 VL - 179 SP - 106099 PB - Elsevier B.V. AN - OPUS4-53583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dariz, P. A1 - Schmid, Thomas T1 - Spurenbestandteile in frühmittelalterlichem Ägyptisch Blau als Informationsträger N2 - Naturwissenschaftliche Belege für die Verwendung von Ägyptisch Blau, dem klassischen Blaupigment der römischen Antike, an frühmittelalterlichen Wandmalereien in Mittel- und Südeuropa sind bisher nur vereinzelt greifbar. Das hier diskutierte monochrom blaue Fragment einer Freskomalerei auf Tünche gehört zum zweiten Kirchenbau von St. Peter ob Gratsch (Südtirol, Norditalien); zumindest der Putzmörtel ist gemäß Radiocarbondatierung im 5. oder 6. Jahrhundert n. Chr. zu verorten. Das flächendeckende Abrastern der Probenoberfläche mittels Ramanmikrospektroskopie vermochte neben dem farbgebenden Cuprorivait (und Pflanzenschwarz aus der Untermalung) 26 begleitende Mineralien bis in den Spurenbereich nachzuweisen. Diese erstaunliche Vielfalt ist nur durch mikrospektroskopische Bildgebung in hoher Ortsauflösung zugänglich, ein solch vertiefter Einblick in die Mineralogie der zugrundeliegenden Rohstoffe als auch Umwandlungsreaktionen während Herstellung, Applikation und Alterung des künstlichen Blaupigmentes also an die Weiterentwicklung der analytischen Verfahren gebunden. Insbesondere die natürlichen Verunreinigungen des Quarzsandes liefern Indizien auf die Produktionsstätte: die beiden Klinopyroxene Augit und Aegirin deuten beispielsweise auf magmatischen Aktivitäten ausgesetzte Ablagerungen (oder auf vulkanische Aktivität bereits im Liefergebiet). Zusammen mit Diopsid und Feldspaten, einschließlich des seltenen Celsian, sind sie der Literatur zufolge charakteristischer Bestandteil von vom Fluss Volturno in den Golf von Gaeta transportierten carbonathaltigen Sedimenten. Im Verein mit der archäologischen Evidenz für die Erzeugung von Ägyptisch Blau in Cumae und Liternum und den übereinstimmenden Ausführungen der beiden römischen Fachschriftsteller Vitruv und Plinius der Ältere spricht dies für ein Fabrikat aus dem Golf von Pozzuoli. Als Kupferquelle wurde angesichts des Nachweises von Chalkosin (und Chalkopyrit) vermutlich ein sulfidisches Kupfererz nach Rosten zu Kupferoxid eingesetzt, als schmelzpunktsenkendes Flussmittel wohl ein gemischt-alkalisches, das heißt eine Mischung von Natrium- und Kaliumsalzen in Form von Pflanzenasche. Zum Teil mit Cuprorivait verwachsene, nicht gänzlich umgesetzte Quarzkristalle bei nur geringsten Spuren von Silikatglas lassen auf eine überwiegende Festkörperreaktion (Festphasensintern) schließen; das Aufschmelzen der Rohstoffe zu Glas dürfte bei der Pigmentsynthese eher eine untergeordnete Rolle gespielt haben. KW - Ägyptisch Blau KW - Ramanmikrospektroskopie KW - Spektroskopische Bildgebung KW - Cuprorivait KW - Amorpher Kohlenstoff PY - 2021 VL - 34 SP - 109 EP - 122 PB - Wernersche Verlagsgeselltschaft CY - Worms AN - OPUS4-53758 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dariz, P. A1 - Schmid, Thomas T1 - Trace compounds in Early Medieval Egyptian blue carry information on provenance, manufacture, application, and ageing N2 - Only a few scientific evidences for the use of Egyptian blue in Early Medieval wall paintings in Central and Southern Europe have been reported so far. The monochrome blue fragment discussed here belongs to the second church building of St. Peter above Gratsch (South Tyrol, Northern Italy, fifth/ sixth century A.D.). Beyond cuprorivaite and carbon black (underpainting), 26 accessory minerals down to trace levels were detected by means of Raman microspectroscopy, providing unprecedented insights into the raw materials blend and conversion reactions during preparation, application, and ageing of the pigment. In conjunction with archaeological evidences for the manufacture of Egyptian blue in Cumae and Liternum and the concordant statements of the antique Roman writers Vitruvius and Pliny the Elder, natural impurities of the quartz sand speak for a pigment produced at the northern Phlegrean Fields (Campania, Southern Italy). Chalcocite (and chalcopyrite) suggest the use of a sulphidic copper ore, and water-insoluble salts a mixed-alkaline flux in the form of plant ash. Not fully reacted quartz crystals partly intergrown with cuprorivaite and only minimal traces of silicate glass portend solid-state reactions predominating the chemical reactions during synthesis, while the melting of the raw materials into glass most likely played a negligible role. KW - Egyptian blue KW - Raman microspectroscopy KW - Spectoscopic imaging KW - Cuprorivaite KW - Amorphous carbon PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537591 DO - https://doi.org/10.1038/s41598-021-90759-6 VL - 11 SP - 1 EP - 12 PB - Nature Portfolio AN - OPUS4-53759 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmid, Thomas A1 - Kraft, Ronja A1 - Dariz, P. T1 - Shedding light onto the spectra of lime - Part 2: Raman spectra of Ca and Mg carbonates and the role of d-block element luminescence N2 - We previously described the observation of a characteristic narrowband red luminescence emission of burnt lime (CaO), whose reason was unknown so far. This study presents Raman spectra of Mg5 CO3)4(OH)2∙4H2O, Mg5(CO3)4(OH)2, MgCO3, CaMgCO3 and CaCO3 (in limestone powder) as well as luminescence spectra of their calcination products. Comparison of the latter revealed MgO:Cr3+ as the source of the red lime luminescence in all studied samples, containing magnesium oxide as major component, minor component or trace. Spectral characteristics and theoretical background of the luminescence emission of d-block elements integrated in crystal lattices are discussed with the aim of sharpening the awareness for this effect in the Raman community and promoting its application in materials analysis. The latter is demonstrated by the Raman microspectroscopic imaging of the distributions of both Raman-active and Raman-inactive phases in clinker remnants in a 19th-century meso Portland cement mortar sample, which contain relatively high amounts of free lime detected in the form of both luminescing CaO and Raman-scattering Ca(OH)2, owing to exposure of the surface of the thin section to humid air. A combination of light and Raman spectroscopy revealed a calcium–magnesium–iron sulphide phase, indicating sulphurous raw materials and/or solid fuels employed in the calcination process, which in contrast to previously described morphologies of sulphides in cement clinker form extensive greenish black layers on free lime crystals. KW - Calcium carbonates KW - Raman spectroscopy KW - Luminescence KW - Magnesium carbonates KW - Meso Portland cement PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537611 DO - https://doi.org/10.1002/jrs.6174 SN - 0377-0486 VL - 52 IS - 8 SP - 1462 EP - 1472 PB - Wiley Analytical Science AN - OPUS4-53761 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmid, Thomas A1 - Hidde, Julia A1 - Grünier, Sophie A1 - Jungnickel, Robert A1 - Dariz, P. A1 - Riedel, Jens A1 - Neuhaus, B. T1 - Ageing effects in mountig media of microscope slide samples from natural history collections: A case study with Canada balsam and Permount™ N2 - Microscope slide collections represent extremely valuable depositories of research material in a natural history, forensic, veterinary, and medical context. Unfortunately, most mounting media of these slides deteriorate over time, with the reason for this not yet understood at all. In this study, Raman spectroscopy, ultraviolet–visible (UV–Vis) spectroscopy, and different types of light microscopy were used to investigate the ageing behaviour of naturally aged slides from museum collections and the experimentally aged media of Canada balsam and Permount™, representing a natural and a synthetic resin, respectively, with both being based on mixtures of various terpenes. Whereas Canada balsam clearly revealed chemical ageing processes, visible as increasing colouration, Permount™ showed physical deterioration recognisable by the increasing number of cracks, which even often impacted a mounted specimen. Noticeable changes to the chemical and physical properties of these mounting media take decades in the case of Canada balsam but just a few years in the case of Permount™. Our results question whether or not Canada balsam should really be regarded as a mounting medium that lasts for centuries, if its increasing degree of polymerisation can lead to a mount which is no longer restorable. KW - Deterioration KW - Microscope slides KW - Mounting media KW - Raman spectroscopy KW - UV–Vis spectroscopy PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537632 DO - https://doi.org/10.3390/polym13132112 VL - 13 IS - 13 SP - 1 EP - 27 PB - MDPI CY - Basel AN - OPUS4-53763 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dariz, P. A1 - Wortmann, U. G. A1 - Vogl, Jochen A1 - Schmid, Thomas T1 - Beautiful Pietàs in South Tyrol (Northern Italy): local or imported works of art? N2 - The study, dedicated to Beautiful Pietàs conserved in South Tyrol (Northern Italy), aims to establish, for the first time, a connection between Austroalpine raw materials and the high-fired gypsum mortars constituting the Gothic figure groups in question. The origin and chronology of this stylistically and qualitatively differing ensemble have been subject of art historical debate for nearly a century. The discourse is dominated by three main hypotheses: itinerary of an Austrian artist versus itinerary of the work of art created in an artist’s workshop in Austria versus itinerary of the stylistic vocabulary via graphical or three-dimensional models. The comparison of the δ34S values and the 87Sr/86Sr ratios of the gypsum mortars and Austroalpine sulphate deposits (in a compilation of own reference samples and literature data) points to the exploitation of sediments in the Salzkammergut and possibly also in the evaporite district of the Eastern Calcareous Alps, thus evidencing the import of the sculptures and not the activities of local South Tyrolean or itinerant artists. Two geochronological units are distinguishable: The Pietà in the Church St. Martin in Göflan can be assigned to Upper Permian raw material, whereas the metrologically consistent sculptures in the Church of Our Lady of the Benedictine Abbey Marienberg and in the Chapel St. Ann in Mölten correlate with deposits of the Early Triassic (or the Lower-Middle Triassic transition). The medieval gypsum mortars also differ in their mineralogical characteristics, i.e. in their geologically related minor components, as in the first case, characterised by a significant proportion of primary anhydrite, natural carbonate impurities mainly consist of calcite (partly converted to lime-lump-like aggregates), whereas in the second group dolomite (or rather its hydration products after pyrometamorphic decomposition) predominates, accompanied by celestine, quartz and potassium feldspar. The Pietà in the Cathedral Maria Himmelfahrt in Bozen turned out to be made of Breitenbrunn calcareous sandstone (Leitha Mountains, Burgenland, Austria), which is why the sample is not considered in the geochemical analysis. KW - High-fired gypsum mortar KW - Sulphur isotope KW - Strontium isotope KW - Polarised light microscopy KW - Raman microspectroscopy PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545610 DO - https://doi.org/10.1186/s40494-022-00678-6 SN - 2050-7445 VL - 10 IS - 1 SP - 1 EP - 17 PB - Springer Nature AN - OPUS4-54561 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kornev, R. A. A1 - Sennikov, P. G. A1 - Gornushkin, Igor B. A1 - Ermakov, A. A. A1 - Shkrunin, V. E. A1 - Polykov, V. S. A1 - Kornev, A. R. A1 - Kornev, K. D. T1 - Laser induced dielectric breakdown as a novel method for the synthesis of molybdenum boride N2 - Laser induced dielectric breakdown (LIDB) on a surface of solid Mo in H2/BF3 atmosphere at 30-760 Torr and in a gaseous mixture MoF6/H2/BF3 + at 760 Torr pressure is tested for synthesis and deposition of superhard molybdenum borides that are needed in many areas of industry and technology. The emission spectra of the plasma and the dynamics of the gas discharge near the substrate are investigated. A comparative analysis of the gas mixture before and after exposure to LIDB plasma is carried out using IR spectroscopy. The conditions for the formation of molybdenum borides are determined. A thermodynamic analysis of the MoF6/H2/BF3 and Mo/H2/BF3 systems is carried out to determine the temperature range for the formation of molybdenum borides and establish the main chemical reactions responsible for their formation. Deposits containing MoB and MoB2 phases are obtained. For the mixture MoF6/H2/BF3, the deposit exhibits an amorphous layered structure, which contains 19.15 wt% F, 30.45% O, and 0.8% Si. For the Mo/H2/BF3 system at the pressures 30 and 160 Torr, nanopowder of molybdenum boride is produced with a characteristic grain size of 100 nm. At pressures above 160 Torr, Mo nanopowder with a grain size <30 nm is obtained. KW - LIDB plasma KW - MoF6 KW - BF3 KW - Hydrogen reduction KW - Molybdenum boride PY - 2022 DO - https://doi.org/10.1007/s11090-021-10224-0 SN - 1572-8986 SP - 1 EP - 18 PB - Springer CY - Dordrecht AN - OPUS4-54290 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kornev, R. A1 - Gornushkin, Igor B. A1 - Nazarov, V. A1 - Shkrunin, V. A1 - Ermakov, A. T1 - Features of hydrogen reduction of SiF4 in ICP plasma N2 - Probe diagnostics is used to determine the electron temperature and electron number density in a low pressure inductively coupled plasma (ICP) ignited in the mixture of SiF4, Ar and H2. Emission spectra of mixtures with different stoichiometry of components are investigated and the electron density distribution function (EDDF) is estimated. The optimal conditions for high conversion of SiF4 into Si are found by studying the dependence of the yield of silicon upon the ratio of reagents. The maximum achieved yield of silicon is 85% under the optimal conditions. Based on the analysis of IR and MS spectra of exhaust gases, 5% of initial SiF4 converts into volatile fluorosilanes. A rate of production of Si is 0.9 g/h at the energy consumption 0.56 kWh /g. KW - Plasma enhanced chemical vapor deposition KW - PECVD KW - Silicon tetrafluoride KW - Emission spectroscopy KW - Probe diagnostics PY - 2022 DO - https://doi.org/10.1016/j.sab.2022.106502 SN - 0584-8547 VL - 195 SP - 106502 PB - Elsevier B.V. AN - OPUS4-55316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Veico, V. P. A1 - Karlagina, Yu. Yu. A1 - Samokhvalov, A. A. A1 - Polyakov, D. S. A1 - Manokhin, S. S. A1 - Radaev, M. M. A1 - Odintsova, G. V. A1 - Gornushkin, Igor B. T1 - Surface Structuring and Reverse Deposition of Nanoporous Titanium Oxides by Laser Ablation of Titanium in Air N2 - The deposition of titanium oxides during titanium laser ablation in air has been experimentally and numerically investigated. A titanium sample was irradiated by nanosecond pulses from an Yb-fber laser with a beam scanned across the sample surface for its texturing. As a result, the hierarchical structure was observed consisting of a microrelief formed by the laser ablation and a nanoporous coating formed by the reverse deposition from the laser induced plasma plume. The chemical and phase composition of the nanoporous coating, as well as the morphology and structure of the surface, were studied using scanning electron microscopy, atomic force microscopy, and X-ray microanalysis. It was found that the deposit consists mostly of porous TiO2 with 26% porosity and inclusions of TiO, Ti2O3, and Ti2O3N. Optical emission spectroscopy was used to control the plasma composition and estimate the effective temperature of plasma plume. The chemical-hydrodynamic model of laser induced plasma was developed to get a deeper insight into the deposition process. The model predicts that condensed titanium oxides, formed in peripheral plasma zones, gradually accumulate on the surface during the plasma plume evolution. A satisfactory agreement between the experimental and calculated chemical composition of the plasma plume as well as between the experimental and calculated composition and thickness of the deposited film was demonstrated. This allows a cautious conclusion that the formation of condensed oxides in the plasma and their consequent deposition onto the ablation surface are among the key mechanisms of formation of porous surface films. KW - Laser ablation KW - Laser induced plasma deposition KW - Surface coating KW - Titanium dioxide KW - Hydrodynamic model KW - Plasma chemistry KW - Emission spectroscopy PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548555 DO - https://doi.org/10.1007/s11090-022-10256-0 VL - 42 IS - 4 SP - 923 EP - 937 PB - Springer AN - OPUS4-54855 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gornushkin, Igor B. A1 - Veiko, V. P. A1 - Karlagina, Y. Y. A1 - Samokhvalov, A. A. A1 - Polyakov, D. S. T1 - Equilibrium model of titanium laser induced plasma in air with reverse deposition of titanium oxides N2 - A chemical-hydrodynamic model of laser induced plasma is developed to study a process of deposition of titanium oxides from titanium laser induced plasma to the titanium target surface. The model is relevant to texturing and coating of titanium bone implants that is done by scanning the ablation laser across implant surfaces. Such the procedure improves the biocompatibility and durability of the implants. The model considers plasma chemical reactions, formation of condensed species inside the plasma plume, and deposition and accumulation of these species on the ablation surface. A chemical part of the model is based on minimization of Gibbs free energy of the chemical system; it is used to calculate the chemical composition of the plasma. A hydrodynamic part uses the 2D fluid-dynamic equations that model a 3D axisymmetric plasma plume and assumes the mass and energy exchange between the plasma and the surface. The initial parameters for the model are inferred from experiment. The model shows that condensed titanium oxides, mostly TiO2, form in a peripheral plasma zone and gradually adhere to the surface during the plasma plume evolution. The model predicts the major component and thickness of the deposit and can be applied for the optimization of experiments aimed at surface modification. KW - Fluid dynamic model KW - Plasma chemistry KW - Laser ablation KW - Laser induced plasma deposition KW - Surface coating KW - Titanium dioxide PY - 2022 DO - https://doi.org/10.1016/j.sab.2022.106449 SN - 0038-6987 SN - 0584-8547 VL - 193 SP - 1 EP - 7 PB - Elsevier CY - Amsterdam AN - OPUS4-54866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gornushkin, Igor B. A1 - Völker, Tobias T1 - Intrinsic Performance of Monte Carlo Calibration-Free Algorithm for Laser-Induced Breakdown Spectroscopy N2 - The performance of the Monte Carlo (MC) algorithm for calibration-free LIBS was studied on the example of a simulated spectrum that mimics a metallurgical slag sample. The underlying model is that of a uniform, isothermal, and stationary plasma in local thermodynamical equilibrium. Based on the model, the algorithm generates from hundreds of thousands to several millions of simultaneous configurations of plasma parameters and the corresponding number of spectra. The parameters are temperature, plasma size, and concentrations of species. They are iterated until a cost function, which indicates a difference between synthetic and simulated slag spectra, reaches its minimum. After finding the minimum, the concentrations of species are read from the model and compared to the certified values. The algorithm is parallelized on a graphical processing unit (GPU) to reduce computational time. The minimization of the cost function takes several minutes on the GPU NVIDIA Tesla K40 card and depends on the number of elements to be iterated. The intrinsic accuracy of the MC calibration-free method is found to be around 1% for the eight elements tested. For a real experimental spectrum, however, the efficiency may turn out to be worse due to the idealistic nature of the model, as well as incorrectly chosen experimental conditions. Factors influencing the performance of the method are discussed. KW - Laser induced breakdown spectroscopy KW - Calibration-free analysis KW - Monte Carlo algorithm PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-558016 DO - https://doi.org/10.3390/s22197149 VL - 22 IS - 19 SP - 7149 PB - MDPI AN - OPUS4-55801 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Völker, Tobias A1 - Gornushkin, Igor B. T1 - Importance of physical units in the Boltzmann plot method N2 - The Boltzmann plot is one of the most widely used methods for determining the temperature in different types of laboratory plasmas. It operates on the logarithm as a function of the dimensional argument, which assumes that the correct physical units are used. In many works using the Boltzmann method, there is no analysis of the dimension of this argument, which may be the cause of a potential error. This technical note offers a brief description of the method and shows how to correctly use physical units when using transcendental functions like the logarithm. KW - Boltzmann plot KW - Laser induced plasma PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-558039 DO - https://doi.org/10.1039/d2ja00241h SP - 1 EP - 3 PB - Royal Society of Chemistry AN - OPUS4-55803 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Martusevich, A. A1 - Kornev, R. A1 - Ermakov, A. A1 - Gornushkin, Igor B. A1 - Nazarov, V. A1 - Shabarova, L. A1 - Shkrunin, V. T1 - Spectroscopy of Laser-Induced Dielectric Breakdown Plasma in Mixtures of Air with Inert Gases Ar, He, Kr, and Xe N2 - The generation of ozone and nitrogen oxides by laser-induced dielectric breakdown (LIDB) in mixtures of air with noble gases Ar, He, Kr, and Xe is investigated using OES and IR spectroscopy, mass spectrometry, and absorption spectrophotometry. It is shown that the formation of NO and NO2 noticeably depends on the type of inert gas; the more complex electronic configuration and the lower ionization potential of the inert gas led to increased production of NO and NO2. The formation of ozone occurs mainly due to the photolytic reaction outside the gas discharge zone. Equilibrium thermodynamic analysis showed that the formation of NO in mixtures of air with inert gases does not depend on the choice of an inert gas, while the equilibrium concentration of the NO+ ion decreases with increasing complexity of the electronic configuration of an inert gas. KW - Laser-induced dielectric breakdown (LIDB) KW - Nitrogen monoxide KW - Nitrogen dioxide KW - Ozone KW - Emission spectroscopy KW - Inert gases KW - Thermodynamic analysis PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568258 DO - https://doi.org/10.3390/s23020932 SN - 1424-8220 VL - 23 IS - 2 SP - 1 EP - 13 PB - MDPI CY - Basel, Switzerland AN - OPUS4-56825 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Völker, Tobias A1 - Gornushkin, Igor B. T1 - Extension of the Boltzmann plot method for multiplet emission lines N2 - The Boltzmann plot method is widely used to determine the temperature of laser induced plasma. It involves the use of individual lines that are not easy to find in complex spectra and/or in the spectral range available. If the number of such lines is not enough to build a reliable Boltzmann plot, overlapping lines are often used, which are separated by software. However, line separation is a rather imprecise procedure, which, in addition, requires significant computational costs. This study proposes an extension of the Boltzmann plot method that allows a specific group of unresolved lines to be included in a Boltzmann plot without the need to separate them. This group of lines are multiplets, lines of the same element with similar upper and lower transition states. The multiplet lines along with the individual lines are included in the algorithm, which also includes a correction for self-absorption and is used to determine the plasma temperature. The algorithm is tested on synthetic spectra which are consistent with the model of a homogeneous isothermal plasma in local thermodynamic equilibrium and is shown to be superior to the standard Boltzmann plot method both in more accurate determination of the plasma temperature and in a significant reduction in the computational time. The advantages and disadvantages of the method are discussed in the context of its applications in laser induced breakdown spectroscopy. KW - LIBS KW - Spectroscopy KW - Boltzmann plot KW - Multiplet KW - Spectral overlap PY - 2023 DO - https://doi.org/10.1016/j.jqsrt.2023.108741 SN - 1879-1352 VL - 310 SP - 1 EP - 5 PB - Elsevier AN - OPUS4-58058 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kornev, Roman A1 - Gornushkin, Igor B. A1 - Shabarova, Lubov A1 - Kadomtseva, Alena A1 - Mochalov, Georgy A1 - Rekunov, Nikita A1 - Romanov, Sergey A1 - Medov, Vitaly A1 - Belousova, Darya A1 - Maleev, Nikita T1 - Plasma-Chemical Disposal of Silicon and Germanium Tetrachlorides Waste by Hydrogen Reduction N2 - The processes of hydrogen reduction of silicon and germanium chlorides under the conditions of high-frequency (40.68 MHz) counteracted arc discharge stabilized between two rod electrodes are investigated. The main gas-phase and solid products of plasma-chemical transformations are determined. Thermodynamic analysis of SiCl4 + H2 and GeCl4 + H2 systems for optimal process parameters was carried out. Using the example of hydrogen reduction of SiCl4 by the method of numerical modeling, gas-dynamic and thermal processes for this type of discharge are investigated. The impurity composition of gas-phase and solid reaction products is investigated. The possibility of single-stage production of high-purity Si and Ge mainly in the form of compact ingots, as well as high-purity chlorosilanes and trichlorogermane, is shown. KW - High-frequency arc discharge KW - Hydrogen reduction KW - Silicon chlorides KW - Germanium chlorides PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594454 DO - https://doi.org/10.3390/sci6010001 VL - 6 IS - 1 SP - 1 EP - 12 PB - MDPI AG AN - OPUS4-59445 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Völker, Tobias A1 - Gornushkin, Igor B. T1 - Investigation of a method for the correction of self-absorption by Planck function in laser induced breakdown spectroscopy N2 - The electron density and temperature of a laser-induced plasma can be determined from the width and intensity of the spectral lines, provided that the corresponding optical transitions are optically thin. However, the lines in laser induced plasma are often self-absorbed. One of the methods of correction of this effect is based on the use of the Planck function and an iterative numerical calculation of the plasma temperature. In this study, the method is further explored and its inherent errors and limitations are evaluated. For this, synthetic spectra are used that fully correspond to the assumed conditions of a homogeneous isothermal plasma at local thermodynamic equilibrium. Based on the error analysis, the advantages and disadvantages of the method are discussed in comparison with other methods of self-absorption correction. KW - LIBS KW - Self-absorption KW - Planck function PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572677 DO - https://doi.org/10.1039/D2JA00352J SN - 0267-9477 SP - 1 EP - 6 PB - Royal Society of Chemistry (RSC) AN - OPUS4-57267 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - van Wasen, S. A1 - You, Yi A1 - Beck, S. A1 - Riedel, Jens A1 - Volmer, D. A. T1 - Miniaturized Protein Digestion Using Acoustic Levitation with Online High Resolution Mass Spectrometry N2 - The combination of acoustically levitated droplets, mid-IR laser evaporation, and subsequent post-ionization by secondary electrospray ionization was applied for monitoring the enzymatic digestion of various proteins. Acoustically levitated droplets are an ideal, wall-free model reactor, readily allowing compartmentalized microfluidic trypsin digestions. Time-resolved interrogation of the droplets yielded real-time information on the progress of the reaction and thus provided insights into reaction kinetics. After 30 min of digestion in the acoustic levitator, the obtained protein sequence coverages were identical to the reference overnight digestions. Importantly, our results clearly demonstrate that the applied experimental setup can be used for the real-time investigation of chemical reactions. Furthermore, the described methodology only uses a fraction of the typically applied amounts of solvent, analyte, and trypsin. Thus, the results exemplify the use of acoustic levitation as a green analytical chemistry alternative to the currently used batch reactions. KW - Acoustic levitation KW - Protein analysis KW - Mass spectrometry PY - 2023 DO - https://doi.org/10.1021/acs.analchem.2c05334 VL - 95 SP - 4190 EP - 4195 PB - ACS Publications AN - OPUS4-57053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Alcalde-Vasquez, R. A1 - Moreno-Pedraza, A. A1 - Rosas-Román, I. A1 - Guillén-Alonso, H. A1 - Riedel, Jens A1 - Partida-Martínez, L. P. A1 - Winkler, R. T1 - MoBiMS: A Modular Miniature Mass Analyzer for the Real-Time 2 Monitoring of Gases and Volatile Compounds in Biological Systems N2 - Living organisms constantly interact with their environment, including through the exchange of gases. Respiration and the release and uptake of volatile organic compounds (VOCs) create dynamic microenvironments in biological systems. Studying the kinetics of volatiles in biological systems requires expensive instruments, and data analysis is challenging. Therefore, we aimed to design a minimal analytical device for measuring the composition of gaseous mixtures in realtime. We built the ‘Modular Biological Mass Spectrometer’ (MoBiMS) from 3D-printed parts and custom sensors to fit a wide array of experimental set-ups. We tested the chemical detection range and temporal resolution of the MoBiMS employing pure compounds and complex biological samples. Compounds with a higher than 0.4 mmHg vapor pressure and a molecular weight up to 154 g/mol were reliably sensed within seconds. The generated electron impact (EI) spectra were directly comparable with standard databases like the NIST EI library. Under a direct analysis approach, the MoBiMS identified the characteristic odor of banana (Musa sp.), that is, isoamyl acetate; tracked the dynamics of CO2 release while the Alka-Seltzer® reaction occurred showed the kinetics of the transient production and consumption of carbon dioxide during photosynthesis. MoBiMS also discriminated between volatile compounds ions coming from tobacco (Nicotiana benthamiana) leaves and the surrounding air through untargeted analysis. The small footprint of the MoBiMS and its relatively low energy consumption facilitate in situ analyses, as an additional gas supply is not necessary with EI ionization. The MoBiMS is easy to assemble, and its construction and operation are very cost-efficient compared to commercial devices. The analytical performance of the MoBiMS is suitable for real-time studies of biological systems, environmental monitoring, and medical diagnostics. KW - Mass spectrometry KW - Instrumentation KW - Miniaturization KW - Volatiles PY - 2022 DO - https://doi.org/10.1016/j.microc.2021.107090 SN - 0026-265X VL - 175 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-56528 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Völker, Tobias A1 - Wilsch, Gerd A1 - Gornushkin, Igor B. A1 - Kratochvilo, L. A1 - Pořízka, P. A1 - Kaiser, J. A1 - Millar, S. A1 - et al., T1 - Interlaboratory comparison for quantitative chlorine analysis in cement pastes with laser induced breakdown spectroscopy N2 - Concrete structures experience severe damage during service, for example due to pitting corrosion of rebars caused by the ingress of chlorine (Cl) into the porous concrete structure. The ingress can be monitored using laser-induced breakdown spectroscopy (LIBS), a recently introduced civil engineering technique used to detect Cl in concrete structures in addition to conventional wet chemistry methods. The key advantages of LIBS are high spatial resolution, which is important when analyzing heterogeneous concrete samples, as well as the almost complete absence of sample preparation. To assess LIBS as a reliable analytical method, its accuracy and robustness must be carefully tested. This paper presents the results of an interlaboratory comparison on the analysis of Cl in cement paste samples conducted by 12 laboratories in 10 countries. Two sets of samples were prepared with Cl content ranging from 0.06 to 1.95 wt% in the training set and 0.23–1.51 wt% in the test set, with additional variations in the type of cement and Cl source (salt type). The overall result shows that LIBS is suitable for the quantification of the studied samples: the average relative error was generally below 15%. The results demonstrate the true status quo of the LIBS method for this type of analysis, given that the laboratories were not instructed on how to perform the analysis or how to process the data. KW - LIBS KW - Interlaboratory comparison KW - Round robin test KW - Cement KW - Chlorine PY - 2023 DO - https://doi.org/10.1016/j.sab.2023.106632 SN - 0584-8547 VL - 202 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-57102 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dariz, P. A1 - Schmid, Thomas T1 - Raman focal point on Roman Egyptian blue elucidates disordered cuprorivaite, green glass phase and trace compounds N2 - The discussed comparative analyses of Roman Imperial pigment balls and fragmentary murals unearthed in the ancient cities of Aventicum and Augusta Raurica (Switzerland) by means of Raman microspectroscopy pertain to a predecessor study on trace compounds in Early Medieval Egyptian blue (St. Peter, Gratsch, South Tyrol, Northern Italy). The plethora of newly detected associated minerals of the raw materials surviving the synthesis procedure validate the use of quartz sand matching the composition of sediments transported by the Volturno river into the Gulf of Gaeta (Campania, Southern Italy) with a roasted sulphidic copper ore and a mixed-alkaline plant ash as fluxing agent. Thus, the results corroborate a monopolised pigment production site located in the northern Phlegrean Fields persisting over the first centuries A.D., this in line with statements of the antique Roman writers Vitruvius and Pliny the Elder and recent archaeological evidences. Beyond that, Raman spectra reveal through gradual peak shifts and changes of band width locally divergent process conditions and compositional inhomogeneities provoking crystal lattice disorder in the chromophoric cuprorivaite as well as the formation of a copper-bearing green glass phase, the latter probably in dependency of the concentration of alkali flux, notwithstanding that otherwise solid-state reactions predominate the synthesis. KW - Raman microspectroscopy KW - Egyptian blue KW - Cuprorivaite PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559028 DO - https://doi.org/10.1038/s41598-022-19923-w SN - 2045-2322 VL - 12 IS - 1 SP - 1 EP - 12 PB - Nature Publishing Group CY - London AN - OPUS4-55902 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Saeidfirozeh, H. A1 - Kubelík, P. A1 - Laitl, V. A1 - Krivkova, A. A1 - Vrabel, J. A1 - Rammelkamp, K. A1 - Schroder, S. A1 - Gornushkin, Igor B. A1 - Kepes, E. A1 - Zabka, J. A1 - Ferus, M. A1 - Porízka, P. A1 - Kaiser, J. T1 - Laser-induced breakdown spectroscopy in space applications: Review and prospects N2 - This review describes the principles and summarizes the challenges of analytical methods based on optical emission spectroscopy (OES) in space applications, with a particular focus on Laser-Induced Breakdown Spectroscopy (LIBS). Over the past decade, LIBS has emerged as a powerful analytical technique for space exploration and In-Situ Resource Utilization (ISRU) of celestial bodies. Its implementation has been suggested for various segments of the Space Resources Value Chain, including prospecting, mining, and beneficiation. Current missions to Mars, including the ChemCam instrument on the Curiosity rover, the SuperCam on the Perseverance rover, and the MarSCoDe on the Zhurong rover, are considered flagship applications of LIBS. Despite neither the Pragyan rover nor the Vikram lander waking from the lunar night, the success of the Chandrayaan-3 mission marks another milestone in the development of LIBS instruments, with further missions, including commercial ones, anticipated. This paper reviews the deployment of LIBS payloads on Mars rovers, upcoming missions prospecting the Moon and asteroids, and LIBS analysis of meteorites. Additionally, it highlights the importance of data processing specific to space applications, emphasizing recent trends in transfer learning. Furthermore, LIBS combined with other spectroscopic techniques (e.g., Raman Spectroscopy, Mass Spectrometry, and Fourier-Transform Infrared Spectroscopy) represents an intriguing platform with comprehensive analytical capabilities. The review concludes by emphasizing the significance of LIBS-based contributions in advancing our understanding of celestial bodies and paving the way for future space exploration endeavors KW - Laser-induced breakdown spectroscopy KW - Mars KW - Moon KW - Asteroids KW - Meteorites KW - Machine learning KW - Transfer learning KW - Raman spectroscopy KW - Mass spectrometry KW - Fourier-transform infrared spectroscopy PY - 2024 DO - https://doi.org/10.1016/j.trac.2024.117991 VL - 181 SP - 1 EP - 22 PB - Elsevier B.V. AN - OPUS4-62142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zöllner, Moritz T. A1 - Dariz, Petra A1 - Riedel, Jens A1 - Schmid, Thomas T1 - Dolomite and Mg Calcite as Mineral Thermometers in Mortar Binders. A High Resolution Raman Spectroscopic Study N2 - This paper suggests the use of high‐resolution Raman scattering bands of MgCa carbonates as posteriori thermometer minerals in archaeometric studies. Therefore, the thermal behavior of two dolomite samples and the hydration and carbonation reaction in air of the decomposition products were investigated by Raman microspectroscopy. The increase in the calcination temperature resulted in the formation of – Raman silent MgO and – inert Mg calcite at 700°C–750°C. In contrast, the decarbonation, hydration, and recarbonation of sample material exposed to 750°C–900°C in a muffle furnace led to the appearance of Mg‐free calcite. High spectral resolution Raman spectroscopy enabled a spectral distinction between these two groups due to differences in the band parameters (peak position, bandwidth) of the vibrational (v1, v4, L) modes of calcite. In combination with Raman microspectroscopic mapping, this spectral information represents a new approach for the estimation of burning temperatures of medieval high‐fired gypsum mortars via natural dolomite impurities. Thus, the results of this work highlight the importance and potential of Raman microspectroscopy as a thermometric tool for elucidating the thermal history of anthropogenic fired materials, with potential applications for archaeometry and art technology, as well as for quality controls in the frame of the production of mineral mortar binders and ceramics or bricks, respectively. KW - Mineral thermometry KW - Raman spectroscopy KW - Dolomite KW - High-fired gypsum mortar PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630270 DO - https://doi.org/10.1002/jrs.6810 SN - 1097-4555 SP - 1 EP - 13 PB - Wiley AN - OPUS4-63027 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Völker, Tobias A1 - Gornushkin, Igor B. T1 - Mass and mole fractions in calibration-free LIBS N2 - This technical note highlights the fact that CF-LIBS algorithms work in mole fractions, while results of spectrochemical analysis are usually reported in mass fractions or mass percent. Ignoring this difference and not converting mole fractions to mass fractions can lead to errors in reported concentrations determined by the CF-LIBS method and inadequate comparison of these concentrations with certified concentrations. Here, the key points of the CF-LIBS algorithm are reproduced and the formulae for converting a mole fraction to a mass fraction and vice versa are given. Several numerical examples are also given, which show that the greater the difference between the molar mass of an individual element in a sample and the average molar mass, the greater the discrepancy between the mole and mass fractions. KW - Spectroscopy KW - Analytical Chemistry KW - LIBS KW - Calibration PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598611 DO - https://doi.org/10.1039/d4ja00028e SN - 0267-9477 VL - 39 IS - 4 SP - 1030 EP - 1032 PB - Royal Society of Chemistry (RSC) AN - OPUS4-59861 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Quackatz, Lukas A1 - Gornushkin, Igor B. A1 - Griesche, Axel A1 - Kannengießer, Thomas A1 - Treutler, Kai A1 - Wesling, Volker T1 - In situ chemical analysis of duplex stainless steel weld by laser induced breakdown spectroscopy N2 - The high corrosion resistance and good mechanical properties of duplex stainless steel (DSS) are due to its special chemical composition, which is a balanced phase ratio of ferrite (α) and austenite (γ). Many industrial applications require the integration of DSS components. For this, Gas tungsten arc welding (GTAW) is an excellent choice, as it allows an automated operation with high reproducibility. However, when the weld pool solidifies, critical ratios of α- and γ- phases can occur, which lead to solidification cracking, increased susceptibility to corrosion, and a decrease in ductility and critical strength. Previous studies have shown that these defects can be caused by the accumulation of manganese and chromium in the heat affected zone (HAZ), requiring ongoing monitoring of this accumulation. A suitable method for such monitoring is laser-induced breakdown spectroscopy (LIBS), which can be used in two operating modes: calibration using standard reference samples and calibration-free. Unlike conventional quantitative LIBS measurements, which require reference samples to generate a calibration curve, calibration-free LIBS (CF-LIBS) allows chemical compositions to be determined solely from the emission spectrum of the plasma. Numerous publications show that CF-LIBS is a fast and efficient analytical method for the quantitative analysis of metal samples. In this work, CF-LIBS is applied to spectra obtained during GTAW DSS welding and the result is compared with those obtained by PLS analysis. A good correlation was found between both types of analysis, demonstrating the suitability of the CF-LIBS method for this application. The CF-LIBS method has a significant advantage over conventional LIBS due to the rapid in situ measurement of concentrations of major alloying elements without calibration procedure. This, combined with fast feedback and appropriate adjustment of welding parameters, helps prevent welding defects. KW - Duplex stainless steels KW - In situ measurement KW - LIBS KW - GMAW PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597940 DO - https://doi.org/10.1016/j.sab.2024.106899 SN - 0584-8547 VL - 214 SP - 1 EP - 7 PB - Elsevier B.V. AN - OPUS4-59794 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chan, George C.-Y. A1 - Hieftje, Gary M. A1 - Omenetto, Nicoló A1 - Axner, Ove A1 - Bengtson, Arne A1 - Bings, Nicolas H. A1 - Blades, Michael W. A1 - Bogaerts, Annemie A1 - Bolshov, Mikhail A. A1 - Broekaert, José A.C. A1 - Chan, WingTat A1 - Costa-Fernández, José M. A1 - Crouch, Stanley R. A1 - De Giacomo, Alessandro A1 - D’Ulivo, Alessandro A1 - Engelhard, Carsten A1 - Falk, Heinz A1 - Farnsworth, Paul B. A1 - Florek, Stefan A1 - Gamez, Gerardo A1 - Gornushkin, Igor B. A1 - Günther, Detlef A1 - Hahn, David W. A1 - Hang, Wei A1 - Hoffmann, Volker A1 - Jakubowski, Norbert A1 - Karanassios, Vassili A1 - Koppenaal, David W. A1 - Kenneth Marcus, R. A1 - Noll, Reinhard A1 - Olesik, John W. A1 - Palleschi, Vincenzo A1 - Panne, Ulrich A1 - Pisonero, Jorge A1 - Ray, Steven J. A1 - Resano, Martín A1 - Russo, Richard E. A1 - Scheeline, Alexander A1 - Smith, Benjamin W. A1 - Sturgeon, Ralph E. A1 - Todolí, José-Luis A1 - Tognoni, Elisabetta A1 - Vanhaecke, Frank A1 - Webb, Michael R. A1 - Winefordner, James D. A1 - Yang, Lu A1 - Yu, Jin A1 - Zhang, Zhanxia T1 - Landmark Publications in Analytical Atomic Spectrometry: Fundamentals and Instrumentation Development N2 - The almost-two-centuries history of spectrochemical analysis has generated a body of literature so vast that it has become nearly intractable for experts, much less for those wishing to enter the field. Authoritative, focused reviews help to address this problem but become so granular that the overall directions of the field are lost. This broader perspective can be provided partially by general overviews but then the thinking, experimental details, theoretical underpinnings and instrumental innovations of the original work must be sacrificed. In the present compilation, this dilemma is overcome by assembling the most impactful publications in the area of analytical atomic spectrometry. Each entry was proposed by at least one current expert in the field and supported by a narrative that justifies its inclusion. The entries were then assembled into a coherent sequence and returned to contributors for a round-robin review. KW - Analytical atomic spectrometry KW - Spectroscopy KW - Instrumental analysis PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621588 DO - https://doi.org/10.1177/00037028241263567 SN - 1943-3530 VL - 78 SP - 1 EP - 456 PB - Sage CY - London AN - OPUS4-62158 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Winckelmann, Alexander A1 - Morcillo Garcia-Morato, Dalia A1 - Richter, Silke A1 - Recknagel, Sebastian A1 - Riedel, Jens A1 - Vogl, Jochen A1 - Panne, Ulrich A1 - Abad Andrade, Carlos Enrique T1 - Determination of lithium in human serum by isotope dilution atomic absorption spectrometry N2 - The therapeutic dose of lithium (Li) compounds, which are widely used for the treatment of psychiatric and hematologic disorders, is close to its toxic level; therefore, drug monitoring protocols are mandatory. Herein, we propose a fast, simple, and low-cost analytical procedure for the traceable determination of Li concentration in human serum, based on the monitoring of the Li isotope dilution through the partially resolved isotope shift in its electronic transition around 670.80 nm using a commercially available high-resolution continuum source graphite furnace atomic absorption spectrometer. With this technique, serum samples only require acidic digestion before analysis. The procedure requires three measurements—an enriched 6Li spike, a mixture of a certified standard solution and spike, and a mixture of the sample and spike with a nominal 7Li/6Li ratio of 0.82. Lanthanum has been used as an internal spectral standard for wavelength correction. The spectra are described as the linear superposition of the contributions of the respective isotopes, each consisting of a spin-orbit doublet, which can be expressed as Gaussian components with constant spectral position and width and different relative intensity, reflecting the isotope ratio in the sample. Both the spectral constants and the correlation between isotope ratio and relative band intensity have been experimentally obtained using commercially available materials enriched with Li isotopes. The Li characteristic mass (mc) obtained corresponds to 0.6 pg. The procedure has been validated using five human serum certified reference materials. The results are metrologically comparable and compatible to the certified values. The measurement uncertainties are comparable to those obtained by the more complex and expensive technique, isotope dilution mass spectrometry. KW - Lithium KW - Human serum KW - Isotope dilution KW - Atomic absorption spectrometry KW - High-resolution continuum source graphite furnace atomic absorption spectrometry PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532446 DO - https://doi.org/10.1007/s00216-021-03636-6 VL - 414 IS - 1 SP - 251 EP - 256 PB - Springer CY - Berlin AN - OPUS4-53244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Winckelmann, Alexander A1 - Nowak, S. A1 - Richter, Silke A1 - Recknagel, Sebastian A1 - Riedel, Jens A1 - Vogl, Jochen A1 - Panne, Ulrich A1 - Abad Andrade, Carlos Enrique T1 - High-Resolution Atomic Absorption Spectrometry Combined With Machine Learning Data Processing for Isotope Amount Ratio Analysis of Lithium N2 - An alternative method for lithium isotope amount ratio analysis based on a combination of high-resolution atomic absorption spectrometry and spectral data analysis by machine learning (ML) is proposed herein. It is based on the well-known isotope shift of approximately 15 pm for the electronic transition 22P←22S at around the wavelength of 670.8 nm, which can be measured by the state-of-the-art high-resolution continuum source graphite furnace atomic absorption spectrometry. For isotope amount ratio analysis, a scalable tree boosting ML algorithm (XGBoost) was employed and calibrated using a set of samples with 6Li isotope amount fractions, ranging from 0.06 to 0.99 mol mol–1, previously determined by a multicollector inductively coupled plasma mass spectrometer (MC-ICP-MS). The calibration ML model was validated with two certified reference materials (LSVEC and IRMM-016). The procedure was applied toward the isotope amount ratio determination of a set of stock chemicals (Li2CO3, LiNO3, LiCl, and LiOH) and a BAM candidate reference material NMC111 (LiNi1/3Mn1/3Co1/3O2), a Li-battery cathode material. The results of these determinations were compared with those obtained by MC-ICP-MS and found to be metrologically comparable and compatible. The residual bias was −1.8‰, and the precision obtained ranged from 1.9 to 6.2‰. This precision was sufficient to resolve naturally occurring variations, as demonstrated for samples ranging from approximately −3 to +15‰. To assess its suitability to technical applications, the NMC111 cathode candidate reference material was analyzed using high-resolution continuum source atomic absorption spectrometry with and without matrix purification. The results obtained were metrologically compatible with each other. KW - Lithium KW - Isotope KW - Machine learning KW - Algorithms KW - Reference material KW - AAS KW - Atomic Absorption Spectrometry PY - 2021 DO - https://doi.org/10.1021/acs.analchem.1c00206 SN - 1520-6882 VL - 93 IS - 29 SP - 10022 EP - 10030 PB - American Chemical Society CY - Washington, DC, USA AN - OPUS4-53028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Li, Xunyu A1 - Riedel, Jens A1 - You, Yi T1 - Practical high-resolution spectroscopy with a spatial heterodyne spectrometer: Determination of instrumental function for lineshape recovery N2 - The spatial heterodyne spectrometer (SHS) is a well-recognized platform for its high resolving power in various use cases of spectroscopy. Same as other spectrometer topologies, the SHS, unfortunately, also suffers from classical challenges such as distorted lineshape due to the instrumental function. The goal of this work is to tackle this persisting issue through a simple numerical approach. With the inherent characteristics of an SHS interferogram, we report the direct extraction and determination of the instrumental function in its numerical representation from an SHS interferogram; this instrumental function was further used for spectral data processing that enables significant improvements in spectral resolution through deconvolution algorithms.Here, we systematically discuss the recognition of the embedded instrumental function among various ingredients within an interferogram. To verify the numerical approach, lithium was chosen as the model sample, resembling the use of SHS in an isotopic analysis application. Specifically, the resonance transition of lithium D-lines (2P1/2,3/2 ← 2S1/2) was selected to assess the performance of the spectral processing. With the spectral deconvolution, the spectral features that represent the 6Li and 7Li were nearly baseline-separated, allowing for the accurate measure of the isotopic abundance without external references or algorithm adjustments (e.g., curve fitting). KW - SHS KW - Isotopic analysis KW - High Resolution PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613401 DO - https://doi.org/10.1016/j.sab.2024.107053 SN - 0584-8547 VL - 221 SP - 1 EP - 5 PB - Elsevier AN - OPUS4-61340 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steinbeck, Christoph A1 - Jung, Nicole A1 - Bach, Felix A1 - Neumann, Steffen A1 - Herres-Pawlis, Sonja A1 - Liermann, Johannes A1 - Koepler, Oliver A1 - Bannwarth, Christoph A1 - Bender, Theo A1 - Bocklitz, Thomas A1 - Boehm, Franziska A1 - Bonatto Minella, Christian A1 - Biedermann, Frank A1 - Brack, Werner A1 - Cunha, Ricardo A1 - Czodrowski, Paul A1 - Eberl, Franziska A1 - Engel, Thomas A1 - Engstfeld, Albert A1 - Fischer, Tillmann G. A1 - Friedrich, Pascal A1 - Glorious, Frank A1 - Golub, Benjamin A1 - Grathwol, Christoph A1 - Haag, Rainer A1 - Hunold, Johannes A1 - Jacob, Christoph A1 - Johannsen, Jochen A1 - Jollife, John A1 - Kast, Stefan A1 - Kettner, Carsten A1 - Kuhn, Stefan A1 - Lanza, Giacomo A1 - Lisec, Jan A1 - Manolikakes, Georg A1 - Mata, Ricardo A1 - Meiler, Jens A1 - Müller, Matthias A1 - Müller-Pfefferkorn, Ralph A1 - Ortmeyer, Jochen A1 - Patterson, Wendy A1 - Pleiss, Jürgen A1 - Riedel, Annalisa A1 - Riedel, Jens A1 - Schatzschneider, Ulrich A1 - Schuster, Leonie A1 - Seeberger, Peter A1 - Seibert, Johann-Nikolaus A1 - Stadler, Peter A1 - Zeitler, Kirsten T1 - Proposal NFDI4Chem 2025-2030 In the National Research Data Infrastructure (NFDI) — Our Vision: All Chemists Publish FAIR Data N2 - The first funding period of NFDI4Chem established a robust foundation for research data management (RDM) in chemistry by promoting FAIR data principles and creating a cohesive infrastructure to capture well-annotated data early in the lab through electronic lab notebooks (ELNs) and making this data available in public repositories. Key achievements include standardised data formats and metadata, a federated repository environment, and improved data visibility and accessibility. Training programs and outreach have significantly increased awareness and adoption of best RDM practices. In the second funding period, the consortium aims to advance these achievements by consolidating this infrastructure, developing a model for its sustainable maintenance and operation, and fostering cultural change for its widespread adoption. Goals include ensuring seamless data workflows from laboratories to open repositories, enhancing interoperability, and supporting innovative research through AI-ready data. The work plan is organised into six task areas (TAs). TA1 (Management) provides leadership and supports all other TAs in achieving their objectives. TA2 (Smart Lab) aims to develop a fully digital research environment, including an ELN as a modular platform. This environment will support data collection, management, storage, analysis, and sharing. Integrating devices and external resources will enable seamless data transfer to repositories. TA3 (Repositories) will consolidate the repository ecosystem. The goal is to integrate repositories into a federated system for better accessibility and interoperability, ensuring long-term data availability and sustainability. TA4 (Metadata, Data Standards, and Publication Standards) focuses on developing and promoting new data and metadata standards in an international community process. This includes applying ontologies to create a semantic foundation for linking research data, making it machine-readable and enabling knowledge graphs. TA5 (Community and Training) is dedicated to fostering a cultural shift towards digital chemistry through continuous engagement, collecting requirements, and providing extensive training and support through workshops and open education resources. It will promote FAIR-compliant machine learning applications, embedding RDM into academic curricula to ensure future scientists are well-versed in these practices. TA6 (Synergies and Cross-Cutting Topics) aims to enhance collaboration across NFDI consortia and beyond. This includes developing ontologies, terminology services, the search service, and other cross-cutting solutions, integrating these developments into existing infrastructure, enabling interdisciplinary data harmonisation and fostering machine learning applications. KW - Research Data Management KW - FAIR KW - Chemistry PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648540 DO - https://doi.org/10.3897/rio.11.e177037 SN - 2367-7163 VL - 11 SP - 1 EP - 100 PB - Pensoft Publishers AN - OPUS4-64854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - You, Yi A1 - Riedel, Jens T1 - Approaching phase-imaging through defocusing shadowgraphy for acoustic resonator diagnosis and the capability of direct index-of-refraction measurements N2 - The visualization of index-of-refraction (IoR) distribution is one of the common methods to investigate fluid flow or pressure fields. While schlieren and shadowgraphy imaging techniques are widely accepted, their inherent limitations often lead to difficulties in elucidating the IoR distribution and extracting the true IoR information from the resulting images. While sophisticated solutions exist, the IoR-gradient-to-image was achieved by purposely introducing a commonly avoided “defect” into the optical path of a conventional coincident schlieren/shadowgraphy setup; the defect is a combination of slight defocusing and the use of non-conjugate optical components. As such, the method presented in this work is referred to as defocusing shadowgraphy, or DF-shadowgraphy. While retaining the ease of a conventional schlieren/shadowgraphy geometry, this DF approach allows direct visualization of complicated resonant acoustic fields even without any data processing. For instance, the transient acoustic fields of a common linear acoustic resonator and a two-dimensional one were directly visualized without inversion. Moreover, the optical process involved in DF-shadowgraphy was investigated from a theoretical perspective. A numerical solution of the sophisticated impulse response function was obtained, which converts the phase distortion into intensity distributions. Based on this solution, the IoRs of various gas streams (e.g., CO2 and isopropanol vapor) were determined from single images. KW - Imaging Technique KW - Phase Imaging KW - Shadowgraphy KW - Schlieren Imaging PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537116 DO - https://doi.org/10.1063/5.0058334 SN - 1089-7623 VL - 92 IS - 10 SP - 103703 PB - AIP Publishing Group AN - OPUS4-53711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - You, Yi A1 - Danischewski, Julia A1 - Molnar, Brian A1 - Riedel, Jens A1 - Shelley, Jacob T1 - Manipulation of Gaseous Ions with Acoustic Fields at Atmospheric Pressure N2 - The ability to controllably move gaseous ions is an essential aspect of ion-based spectrometry (e.g., mass spectrometry and ion mobility spectrometry) as well as materials processing. At higher pressures, ion motion is largely governed by diffusion and multiple collisions with neutral gas molecules. Thus, high-pressure ion optics based on electrostatics require large fields, radio frequency drives, complicated geometries, and/or partially transmissive grids that become contaminated. Here, we demonstrate that low-power standing acoustic waves can be used to guide, block, focus, and separate beams of ions akin to electrostatic ion optics. Ions preferentially travel through the static-pressure regions (“nodes”) while neutral gas does not appear to be impacted by the acoustic field structure and continues along a straight trajectory. This acoustic ion manipulation (AIM) approach has broad implications for ion manipulation techniques at high pressure, while expanding our fundamental understanding of the behavior of ions in gases. KW - Ion mobility spectrometry KW - Acoustic KW - Mass spectrometry PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600704 DO - https://doi.org/10.1021/jacs.4c01224 SP - 1 EP - 6 PB - ACS Publications AN - OPUS4-60070 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - van Wasen, S. A1 - You, Yi A1 - Beck, S. A1 - Riedel, Jens A1 - Volmer, D. T1 - Quantitative Analysis of Pharmaceutical Drugs Using a Combination of Acoustic Levitation and High Resolution Mass Spectrometry N2 - A combination of acoustic levitation, laser vaporization, and atmospheric pressure chemical ionization mass spectrometry (APCI-MS) is presented in this study that enabled sensitive analysis of pharmaceutical drugs from an aqueous sample matrix. An unfocused pulsed infrared laser provided contactless sample desorption from the droplets trapped inside an acoustic levitator by activation of the OH stretching band of aqueous and alcoholic solvents. Subsequent atmospheric pressure chemical ionization was used between the levitated droplet and the mass spectrometer for postionization. In this setup, the unfocused laser gently desorbed the analytes by applying very mild repulsive forces. Detailed plume formation studies by temporally resolved schlieren experiments were used to characterize the liquid gas transition in this process. In addition, the role of different additives and solvent composition was examined during the ionization process. The analytical application of the technique and the proof-of-concept for quantitative analysis were demonstrated by the determination of selected pharmaceutical drugs in aqueous matrix with limits of quantification at the lower nanomolar level and a linear dynamic range of 3–4 orders of magnitude. KW - Atmospheric Pressure Chemical Ionization KW - Ultrasonic Levitation KW - Mass Spectrometry KW - Laser Desorption PY - 2021 DO - https://doi.org/10.1021/acs.analchem.1c00762 VL - 93 IS - 15 SP - 6019 EP - 6024 PB - ACS AN - OPUS4-52470 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Riedel, Jens A1 - Hufgard, Josefin A1 - You, Yi T1 - LIBS at high duty-cycles: effect of repetition rate and temporal width on the excitation laser pulses N2 - Laser-induced breakdown spectroscopy (LIBS) is becoming a more mature technology every year with new variants such as laser ablation molecular isotopic spectrometry, reheating by various discharge techniques, and multiple pulse excitation schemes, in which sometimes lasers of different pulse lengths are used. However, lasers with inherent parameters like pulse length and repetition rate are still almost exclusively employed. Recent years have witnessed the advent of novel high-repetition-rate laser concepts for machining processes, like welding, milling, and engraving. Here, a comprehensive study of single-pulse LIBS spectra of a single aluminum target is presented to showcase the applicability of flexible high duty-cycle master oscillator power amplifier (MOPA) lasers. Although traditional flashlamp-pumped Fabry–Pérot lasers only permit a variation in the pulse energy and are operated at very low duty-cycles, MOPA lasers add repetition rate and pulse length as variable parameters. A thorough analysis of the temporal plasma behavior revealed the emission dynamic to closely match the excitation laser pulse pattern. An aluminum sample’s spectral response was shown to be significantly impacted by variations in both rate and length. Although the spectral emission strength of the elemental lines of Al, Sr, and Ca all peaked at slightly different parameter settings, the strongest impact was found on the relative abundance of molecular AlO bands. Unlike in previous laser ablation molecular isotopic spectrometry (LAMIS) publications, the latter could be readily detected with a good intensity and well-resolved spectral features without any temporal gating of the detector. This finding, together with the fact that MOPA lasers are both inexpensive and dependable, makes for a promising combination for future studies including the detection of diatomic band structures. KW - Laser-induced breakdown spectroscopy KW - LIBS PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-583300 DO - https://doi.org/10.3389/fphy.2023.1241533 SN - 2296-424X VL - 11 SP - 1 EP - 8 AN - OPUS4-58330 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - van Wasen, S. A1 - You, Yi A1 - Beck, S. A1 - Riedel, Jens A1 - Volmer, D. A. T1 - Laser Ablation Secondary Electrospray Ionization for In Situ Mass Spectrometric Interrogation of Acoustically-Levitated Droplets N2 - The composition of acoustically levitated droplets was probed by a novel combination of mid-IR laser evaporation and subsequent postionization via secondary electrospray ionization. The combination of microliter samples and subnanoliter sampling provided time-resolved interrogation of droplets and allowed for a kinetic investigation of the laser-induced release of the analyte, which was found to strongly depend on the analytes. The observed substancespecific delayed release of the analytes permitted baseline-separated discrimination of the analytes, ideal for the study of complex samples. The additionally applied postionization scheme was found to enable efficient detection of small volatile compounds as well as peptides. The detection of small molecules and peptides occurred under very different sampling geometries, pointing to two distinct underlying ionization mechanisms. Overall, our results suggest that the experimental setup presented in this study can serve as a widely applicable platform to study chemical reactions in acoustically levitated droplets as model reactors. KW - Acoustic levitation KW - Mass spectrometry KW - Electrospray KW - Laser ablation PY - 2022 DO - https://doi.org/10.1021/acs.analchem.2c03800 SN - 0003-2700 VL - 2022 SP - 1 EP - 5 PB - ACS Publications CY - Washington AN - OPUS4-56531 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Xue, Boyang A1 - Wang, Zhangjun A1 - Zhu, Tao A1 - Gu, Yezhen A1 - Sun, Weihong A1 - Chen, Chao A1 - Li, Zhigang A1 - Riedel, Jens A1 - You, Yi T1 - High repetition-rate laser-induced breakdown spectroscopy combined with two-dimensional correlation method for analysis of sea-salt aerosols N2 - Laser-induced breakdown spectroscopy (LIBS) offers a tantalizing glimpse into real-time, on-the-spot aerosol analysis. Yet, the reliance on traditional lasers, with their limitations in energy and frequency, hampers optimal sample handling, dissociation, and excitation. To address those challenges, we propose a novel tactic: utilize a high repetition-rate (rep.-rate) laser with low pulse energy in combination with the two-dimensional correlation (2D-corr.) technique for sea-salt aerosols analyses. By examining the emission patterns from both the laser pulse train and individual pulses, we recognize distinctive analyte-specific rep.-rate responses, which allowed spectral reconstruction of analytes, avoiding background interferences. This discovery enabled the rep.-rate modulation for a 2D-corr. spectroscopy workflow. Consequently, we successfully differentiated between particle-related and air-species-related spectral components, obviating expensive spectrometers or intensified image detectors. For instance, the Na I at 589 nm stemming from aerosols exhibited an entirely different correlation contribution compared to O I at 777 nm, resulting in reconstructed clean aerosol-spectra without spectral peaks originated from air species. This 2D-corr. aerosol LIBS approach shows promising analytical potential streamlining aerosol particle analysis. KW - LIBS KW - Aerosol PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613392 DO - https://doi.org/10.1016/j.sab.2024.107048 SN - 0584-8547 VL - 221 SP - 1 EP - 8 PB - Elsevier AN - OPUS4-61339 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Li, Xunyu A1 - Riedel, Jens A1 - You, Yi T1 - Spectrally resolved lithium isotope quantification through high-resolution spatial heterodyne spectrometry N2 - Isotope ratio determination of lithium is increasingly important in fields ranging from geochemistry to battery diagnostics. While mass spectrometry remains the gold standard, it is costly, cumbersome, and incompatible with portable or inline implementations. Optical emission spectroscopy presents an appealing alternative. However, it is traditionally limited by insufficient spectral resolution or resolving power to separate lithium isotope emissions due to their generalized designs for a wide spectral range; this often requires overly complicated algorithms to overcome the instrumental drawbacks. (79) Results Here, we report a high-resolution optical method for lithium isotope quantification using a custom-built spatial heterodyne spectrometer (SHS) combined with a reduced-pressure glow discharge source. This configuration yielded a resolving power of 189,000 and enabled baseline resolution of lithium d-line emission features even without the need for preliminary data processing. Despite the inherent low sensitivity of SHS, a detection limit of 30 pmol was achieved using a standard industrial camera. To improve quantitative accuracy, we introduced a deconvolution-based spectral lineshape recovery technique alongside a bootstrapping-based error propagation strategy. These methods facilitated robust isotope ratio calibration using both peak-height and peak-area metrics. The SHS platform additionally enabled the determination of relative transition probabilities, suggesting the feasibility of calibration-free operation. This work demonstrates the practical viability of SHS for high-specificity, high-resolution lithium isotope analysis. The approach is compact, potentially field-deployable, and adaptable to other elements with optically resolvable isotope shifts, offering a route toward accessible and calibration-free optical isotopic analyses. KW - SHS KW - Isotope KW - High-resolution spectroscopy PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-635139 DO - https://doi.org/10.1016/j.aca.2025.344329 SN - 1873-4324 VL - 1368 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-63513 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mohan, M. A1 - Prochazka, D. A1 - You, Yi A1 - Riedel, Jens A1 - Gornushkin, Igor A1 - Rocnakova, I. A1 - Papula, M. A1 - Porízka, P. A1 - Kaizer, J. T1 - Investigating plasma morphology at material boundaries under varying ambient pressures N2 - Laser-Induced Breakdown Spectroscopy (LIBS) is a widely used technique for elemental analysis. The analysis of the obtained LIBS spectra generally assumes plasma homogeneity. However, using focused laser beams for interrogation, LIBS probes materials on the microscale and is, thus, prone to artefacts from sample heterogeneities on the micrometer scale. An ablation at a material boundary of two matrices may result in a significant inhomogeneity in the plasma plume, which can severely impact the accuracy of quantitative analysis. Since this propagation of the surface morphology into the plasma plume is driven by the plasma expansion, its final impact is strongly pressure dependent. This study examines the influence of varying ambient pressures (7–1000 mbar) on plasma morphology, spectral characteristics, and key plasma properties such as electron number density at a well-defined Cu–Sn boundary, in comparison with the results obtained using homogeneous alloys. Several approaches of plasma imaging with bandpass filters, spectroscopy, and Radon transform-based 3D reconstruction were employed to analyze elemental distribution, signal-to-noise (SNR) and signal-to-background (SBR) ratios, as well as electron number densities. The 3D reconstructions revealed a pronounced plasma asymmetry for the ablation at the material boundary, in contrast to the near-axial symmetry observed for the ablation of homogeneous alloys. At lower pressures, this distinct elemental separation in plasma persisted, while higher pressures led to an increased collisional mixing and homogenization. SNR and SBR were consistently lower for ablation at the boundary compared to homogeneous samples. These findings highlight how boundary ablation contributes to plasma inhomogeneities in LIBS analysis of heterogeneous materials and emphasize the need to account for these effects when using LIBS for elemental mapping of fine heterogeneous structures. KW - Laser-induced breakdown spectroscopy KW - Plasma inhomogeneity KW - Plasma tomography KW - Radon transform KW - Material boundaries KW - Ambient pressure effects PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634777 DO - https://doi.org/10.1016/j.talanta.2025.128377 SN - 1873-3573 VL - 295 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-63477 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - You, Yi A1 - Xue, Boyang A1 - Riedel, Jens T1 - Enhancement of LIBS plasma in air with organic solvent vapors N2 - Laser-induced breakdown spectroscopy (LIBS) offers versatile, field-deployable elemental analysis; however, compact, high-repetition-rate nanosecond laser systems typically face constraints in power consumption and size, often compromising emission intensity and thus analytical performance. We demonstrate a significant improvement in LIBS signals through the controlled introduction of common organic solvent vapors into a sheath gas, with a diode-pumped solid-state laser (1064 nm, 2–28 kHz repetition rate, 450–600-μJ pulse energy). Optical and acoustic diagnostics reveal up to ca. 40-fold enhancement of the N II emission line at 567 nm when ambient air serves as the analyte. Maximal enhancement occurs at intermediate repetition rates of ca. 15 kHz, particularly at pulse energies approaching the optical breakdown threshold; this observation suggests a viable strategy for operating LIBS at lower pulse energies and higher repetition rates. Enhancement effects scale jointly with both vapor pressure and ionization energy of the organic species, with acetone and toluene markedly outperforming methanol and isopropanol. These findings provide a rational foundation for significantly improving the analytical performance of portable LIBS instruments without exceeding platform-specific constraints. KW - LIBS PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653758 DO - https://doi.org/10.1016/j.sab.2025.107309 SN - 0584-8547 VL - 236 SP - 1 EP - 6 PB - Elsevier B.V. AN - OPUS4-65375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bayerlein, Bernd A1 - Hanke, T. A1 - Muth, Thilo A1 - Riedel, Jens A1 - Schilling, Markus A1 - Schweizer, C. A1 - Skrotzki, Birgit A1 - Todor, A. A1 - Moreno Torres, Benjami A1 - Unger, Jörg F. A1 - Völker, Christoph A1 - Olbricht, Jürgen T1 - A Perspective on Digital Knowledge Representation in Materials Science and Engineering N2 - The amount of data generated worldwide is constantly increasing. These data come from a wide variety of sources and systems, are processed differently, have a multitude of formats, and are stored in an untraceable and unstructured manner, predominantly in natural language in data silos. This problem can be equally applied to the heterogeneous research data from materials science and engineering. In this domain, ways and solutions are increasingly being generated to smartly link material data together with their contextual information in a uniform and well-structured manner on platforms, thus making them discoverable, retrievable, and reusable for research and industry. Ontologies play a key role in this context. They enable the sustainable representation of expert knowledge and the semantically structured filling of databases with computer-processable data triples. In this perspective article, we present the project initiative Materials-open-Laboratory (Mat-o-Lab) that aims to provide a collaborative environment for domain experts to digitize their research results and processes and make them fit for data-driven materials research and development. The overarching challenge is to generate connection points to further link data from other domains to harness the promised potential of big materials data and harvest new knowledge. KW - Data infrastructures KW - Digital representations KW - Digital workflows KW - Knowledge graphs KW - Materials informatics KW - Ontologies KW - Vocabulary providers PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546729 DO - https://doi.org/10.1002/adem.202101176 SN - 1438-1656 SP - 1 EP - 14 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-54672 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Li, Xunyu A1 - Riedel, Jens A1 - You, Yi T1 - Determination of broadband-light atomic absorption through interferometric spectrometry with a spatial heterodyne spectrometer N2 - A spatial heterodyne spectrometer (SHS) was combined with a flame atomic absorption (FAA) setup to reveal the analytical potential of SHS to be used as a tool for high-resolution atomic absorption studies. Exploiting the advances in modern computational power, the spectral information encoded in the interferograms was extracted and separated. Consequently, unseeable interferometric ingredients corresponding to narrow-band absorption lines could be recognized. Namely, a single SHS absorption interferogram simultaneously contains both illumination background and absorption information, which can be distinguished through a series of computational steps. In the examples given by this work, we demonstrate the construction of Na absorbance spectra from a single image. The described single-image approach can be used to investigate highly dynamic systems, whereby background collections can be obviated. KW - Optical Spectrometry KW - Spatial Heterodyne Spectrometry KW - Atomic Absorption PY - 2023 DO - https://doi.org/10.1039/D2JA00367H VL - 38 IS - 5 SP - 1088 EP - 1096 PB - Royal Society of Chemistry (RSC) AN - OPUS4-58332 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Danischewski, Julia L. A1 - You, Yi A1 - Bauer, Lauren A1 - Riedel, Jens A1 - Shelley, Jacob T. T1 - Use of Resonant Acoustic Fields as Atmospheric-Pressure Ion Gates N2 - Ion optics are crucial for spectrometric methods such as mass spectrometry (MS) and ion mobility spectrometry (IMS). Among the wide selection of ion optics, temporal ion gates are of particular importance for time-of-flight MS (TOF-MS) and drift-tube IMS. Commonly implemented as electrostatic ion gates, these optics offer a rapid, efficient means to block ion beams and form discrete ion packets for subsequent analysis. Unfortunately, these devices rely on pulsed high voltage sources and are not fully transparent, even in their open state, which can lead to ion losses and contamination. Here, a novel atmospheric-pressure ion gate based on a resonant acoustic field structure is described. This effect was accomplished through the formation of a resonant, standing acoustic wave of alternating nodes and antinodes. Alignment of an atmospheric-pressure gaseous ion beam with an antinode, i.e. a region of transient pressure, of the acoustic structure acted as a gate and blocked ions from impinging on ion-selective detectors, such as a mass spectrometer and a Faraday plate. The velocity of the ion stream and acoustic power were found to be critical parameters for gating efficiency. In the presence of an acoustic field (i.e., a closed gate), ion signals decreased by as much as 99.8% with a response time faster than the readout of the ion-measurement devices used here (ca. 75 ms). This work demonstrates the basis for a low-cost, acoustic ion gate, which is optically transparent and easily constructed with low-power, off-the-shelf components, that could potentially be used with MS and IMS instrumentation. KW - Acoustic Ion Manipulation PY - 2025 DO - https://doi.org/10.1021/acs.analchem.4c05493 SN - 1520-6882 VL - 97 IS - 5 SP - 2890 EP - 2898 PB - American Chemical Society AN - OPUS4-62648 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Miliūtė, Aistė A1 - Bustamante, Joana A1 - Karafiludis, Stephanos A1 - Zöllner, Moritz A1 - Eddah, Mustapha A1 - Emmerling, Franziska A1 - Mieller, Björn A1 - George, Janine A1 - Stawski, Tomasz M. T1 - Synthesis and phase purity of the negative thermal expansion material ZrV2O7 N2 - Synthesis of pure, homogeneous, and reproducible materials is key for the comprehensive understanding, design, and tailoring of material properties. In this study, we focus on the synthesis of ZrV2O7, a material known for its negative thermal expansion properties. We investigate the influence of solid-state and wet chemistry synthesis methods on the purity and homogeneity of ZrV2O7 samples. Our findings indicate that different synthesis methods significantly impact the material's characteristics. The solid-state reaction provided high-purity material through extended milling time and repeated calcination cycles, while the sol-gel reaction enabled a “near-atomic” level of mixing and, therefore, homogenous phase-pure ZrV2O7. We confirmed purity via X-ray diffraction and Raman spectroscopy, highlighting differences between phase-pure and multiphase ceramics. These analytical techniques allowed us to distinguish subtle differences in the structure of the material. Based on ab initio simulated phonon data, we were able to interpret the Raman spectra and visualise Raman active atom vibrations. We show that phase purity enables the unbiased characterisation of material properties such as negative thermal expansion. KW - NTE KW - Sol-gel KW - Solid-state KW - Ab-initio KW - XRD KW - Raman PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624013 DO - https://doi.org/10.1039/d4tc04095c SN - 2050-7534 SP - 1 EP - 13 PB - Royal Society of Chemistry (RSC) AN - OPUS4-62401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Karafiludis, Stephanos A1 - Kochovski, Z. A1 - Scoppola, E. A1 - Retzmann, Anika A1 - Hodoroaba, Vasile-Dan A1 - ten Elshof, J. E. A1 - Emmerling, Franziska A1 - Stawski, Tomasz Maciej T1 - Nonclassical Crystallization Pathway of Transition Metal Phosphate Compounds N2 - Here, we elucidate nonclassical multistep crystallization pathways of transition metal phosphates from aqueous solutions. We followed precipitation processes of M-struvites, NH4MPO4·6H2O, and M-phosphate octahydrates, M3(PO4)2·8H2O, where M = Ni, Co, or NixCo1–x, by using in situ scattering and spectroscopy-based techniques, supported by elemental mass spectrometry analyses and advanced electron microscopy. Ni and Co phosphates crystallize via intermediate colloidal amorphous nanophases, which change their complex structures while agglomerating, condensing, and densifying throughout the extended reaction times. We reconstructed the three-dimensional morphology of these precursors by employing cryo-electron tomography (cryo-ET). We found that the complex interplay between metastable amorphous colloids and protocrystalline units determines the reaction pathways. Ultimately, the same crystalline structure, such as struvite, is formed. However, the multistep process stages vary in complexity and can last from a few minutes to several hours depending on the selected transition metal(s), their concentration, and the Ni/Co ratio. KW - Non-classical crystallization theory KW - Transition metals KW - Phosphates KW - Amorphous phases KW - Intermediate phases PY - 2023 DO - https://doi.org/10.1021/acs.chemmater.3c02346 SN - 1520-5002 VL - 35 IS - 24 SP - 10645 EP - 10657 PB - American Chemical Society (ACS) CY - Washington D.C. AN - OPUS4-59135 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Henning, Thorsten A1 - Goerdeler, Cornelius A1 - El-Khatib, Ahmed H. A1 - Meyer, Klas A1 - Bruer, Gustav G. A1 - Abraham, Klaus A1 - Monien, Bernhard T1 - Characterization and quantitation of urinary metabolites of 3-monochloropropane-1,2-diol (3-MCPD) in rats N2 - Fatty acid esters of 3-monochloropropane-1,2-diol (3-MCPD) are heat-induced contaminants formed from fats and sodium chloride. The mode of action for the 3-MCPD mediated induction of renal tubule neoplasms in rats is still unclear, which is in part due to lacking metabolism data. In the current study, urinary metabolites were identified by one- and two-dimensional 13C nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry following oral administration of 3-MCPD or [13C3]3-MCPD in rats. In addition to 3-MCPD itself, nine metabolites were identified. Four of those, N-acetyl-S-(2,3-dihydroxypropyl)cysteine (DHPMA), 3-MCPD sulfate, β-chlorolactic acid (β-ClLA) and oxalic acid have been reported before. Five novel metabolites in rat urine were thiodiglycolic acid (TDGA), thionyldiglycolic acid (TNDGA), 3-MCPD glucuronide (at least three isomers), 3-carboxy-2-hydroxypropyl mercapturic acid (CHPMA), and 3-(S-carboxymethyl)mercaptolactic acid (CMMLA). Only three metabolites were excreted at mean dose ratios > 1% (after treatment with 50 mg 3-MCPD/kg body weight in male and female rats), i.e. 3-MCPD (7.3%, 9.7%), DHPMA (3.5%, 1.7%) and TDGA (1.1%, 4.0%). The overall mean dose excretion in urine samples (males: 12.2%, females: 16.3%) supported hypotheses on formation of conjugates/adducts of reactive metabolites and the possibility that dechlorination leads to suitable building blocks for amino acid and fatty acid synthesis. The identification of TDGA indicated the interim formation 2-chloroacetaldehyde, previously identified to mediate specific nephrotoxic effects of the cytostatic ifosfamide in rats. KW - 3-Monochloropropane-1,2-diol KW - 3-MCPD KW - Metabolism KW - Urine PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-657230 DO - https://doi.org/10.1007/s00204-026-04318-x SP - 1 EP - 17 PB - Springer-Verlag GmbH CY - Heidelberg AN - OPUS4-65723 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Martins, Ines A1 - Al-Sabbagh, Dominik A1 - Bentrup, U. A1 - Marquardt, Julien A1 - Schmid, Thomas A1 - Scoppola, E. A1 - Kraus, Werner A1 - Stawski, Tomasz A1 - de Oliveira Guilherme Buzanich, Ana A1 - Yusenko, Kirill A1 - Weidner, Steffen A1 - Emmerling, Franziska T1 - Formation Mechanism of a Nano-Ring of Bismuth Cations and Mono-Lacunary Keggin-Type Phosphomolybdate N2 - A new hetero-bimetallic polyoxometalate (POM) nano-ring was synthesized in a one-pot procedure. The structure consists of tetrameric units containing four bismuth-substituted monolacunary Keggin anions including distorted [BiO8] cubes. The nano-ring is formed via self-assembly from metal precursors in aqueous acidic medium. The compound (NH4)16[(BiPMo11O39)4] ⋅ 22 H2O; (P4Bi4Mo44) was characterized by single-crystal X-ray diffraction, extended X-ray absorption fine structure spectroscopy (EXAFS), Raman spectroscopy, matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF), and thermogravimetry/differential scanning calorimetry mass spectrometry (TG-DSC-MS). The formation of the nano-ring in solution was studied by time-resolved in situ small- and wide-angle X-ray scattering (SAXS/WAXS) and in situ EXAFS measurements at the Mo−K and the Bi−L3 edge indicating a two-step process consisting of condensation of Mo-anions and formation of Bi−Mo-units followed by a rapid self-assembly to yield the final tetrameric ring structure. KW - Bismuth KW - In situ EXAFS KW - In situ SAXS/WAXS KW - Lacunary Keggin ion KW - Polyoxometalates KW - Self-assembly PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546823 DO - https://doi.org/10.1002/chem.202200079 SN - 0947-6539 VL - 28 IS - 27 SP - 1 EP - 7 PB - Wiley-VCH CY - Weinheim AN - OPUS4-54682 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -