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Nanoindentation, laser ablation inductively coupled plasma mass spectroscopy and weighing ion-spiked organic matrix standards revealed structure-property relations in the microscopic jaw structures of a cosmopolitan bristle worm, Platynereis dumerilii. Hardness and elasticity values in the jaws’ tip region, exceeding those in the center region, can be traced back to more metal and halogen ions built into the structural protein matrix. Still, structure size appears as an even more relevant factor governing the hardness values measured on bristle worm jaws across the genera Platynereis, Glycera and Nereis. The square of the hardness scales with the inverse of the indentation depth, indicating a Nix-Gao size effect as known for crystalline metals. The limit hardness for the indentation depth going to infinity, amounting to 0.53 GPa, appears to be an invariant material property of the ion-spiked structural proteins likely used by all types of bristle worms. Such a metal-like biogenic material is a major source of bio-inspiration.

Kathrin Chlench-Priber, Marco Heiles, Sven Limbeck und Simone Schultz-Balluff, Was ist historische Wissens- und Gebrauchsliteratur? Tagungskonzept und Programm, in: Netzwerk Historische Wissens- und Gebrauchsliteratur, zuerst Veröffentlicht am 13.06.2022, aktualisierte Version vom 07.11.2022, https://hwgl.hypotheses.org/1801. Tagungskonzept und Programm Die Tagung ist eine Veranstaltung des Netzwerks Historische Wissens- und Gebrauchsliteratur. Dieses Netzwerk, zunächst ein informeller Zusammenschluss von Nachwuchs- und akademisch bereits institutionalisierten Wissenschaftler*innen vornehmlich aus der germanistischen Sprach- und Literaturwissenschaft mit Schwerpunkten in Mittelalter und Früher Neuzeit, hat sich 2020 die Form des eingetragenen Vereins gegeben (Selbstdarstellung und Mitgliederliste mit Projekten und Publikationen: https://hwgl.hypotheses.org). Ziel ist die Förderung der Erforschung der historischen Wissens- und Gebrauchsliteratur und des wissenschaftlichen Austausches darüber. Ein konkretes Vorhaben ist die Herausgabe eines Forschungs- und Methodenhandbuchs zum Thema. Diesen Zweck verfolgt auch die beantragte Tagung: die grundlegende literaturtheoretische Klärung von Begriff und Gegenstand der historischen Wissens- und Gebrauchsliteratur sowie die Parameter der Bildung von Textkorpora als empirische Grundlage der Forschung. Die externen Beiträger*innen geben mit ihren Grundsatzreferaten Impulse in das Netzwerk, Netzwerkmitglieder geben strukturierte Auskünfte über ihre konkreten Forschungsgegenstände. Am Ende der Tagung sollen die geschärfte Begrifflichkeit und Konzeption von Wissen, Gebrauch und Korpusbildung sowie eine dementsprechend systematische Gliederung des Handbuchs stehen. Die Referate bilden idealerweise die Ausgangspunkte für Handbuchartikel.

The determination of mineral dust and elemental carbon in snow samples is of great interest, as both compounds are known as light absorbing snow impurities. Different analytical methods have to be used to quantify both compounds. Still, the occurrence of mineral dust, which contains hematite, leads to a bias in the quantification of elemental carbon via thermal-optical analysis. Here we present an approach which utilizes this interference to determine the concentration of hematite via thermal-optical analysis using a Lab OC/EC Aerosol Analyzer (Sunset Laboratory Inc.) and the EUSAAR2 protocol. Therefore, the temperature dependency of the transmittance signal determined during the calibration phase, i.e. when all carbonaceous compounds are already removed, is evaluated. Converting the transmittance signal into an attenuation, a linear relationship between this attenuation and the hematite loading is obtained for loadings ranging from 10 to 100 µgFe cm-2. Furthermore, the approach allows to identify samples which need to be re-evaluated, as the analysis of elemental carbon is biased by mineral dust. We discuss the successful application of the method, designed for snow samples, to ambient air samples containing mineral dust, and the limitations of the method when other iron compounds besides hematite are present.

The increased demand for sustainability requires, among others, the development of new materials with enhanced corrosion resistance. Transition metal diborides are exceptional candidates, as they exhibit fascinating mechanical and thermal properties. However, at elevated temperatures and oxidizing atmospheres, their use is limited due to the fact of their inadequate oxidation resistance. Recently, it was found that chromium diboride doped with silicon can overcome this limitation. Further improvement of this protective coating requires detailed knowledge regarding the composition of the forming oxide layer and the change in the composition of the remaining thin film. In this work, an analytical method for the quantitative measurement of depth profiles without using matrix-matched reference materials was developed. Using this approach, based on the recently introduced online-LASIL technique, it was possible to achieve a depth resolution of 240 nm. A further decrease in the ablation rate is possible but demands a more sensitive detection of silicon. Two chromium diboride samples with different Si contents suffering an oxidation treatment were used to demonstrate the capabilities of this technique. The concentration profiles resembled the pathway of the formed oxidation layers as monitored with transmission electron microscopy. The stoichiometry of the oxidation layers differed strongly between the samples, suggesting different processes were taking place. The validity of the LASIL results was cross-checked with several other analytical techniques.

The Groningen gas field in the Netherlands is experiencing induced seismicity as a result of ongoing depletion. The physical mechanisms that control seismicity have been studied through rock mechanical experiments and combined physical-statistical models to support development of a framework to forecast induced-seismicity risks. To investigate whether machine learning techniques such as Random Forests and Support Vector Machines bring new insights into forecasts of induced seismicity rates in space and time, a pipeline is designed that extends time-series analysis methods to a spatiotemporal framework with a factorial setup, which allows probing a large parameter space of plausible modelling assumptions, followed by a statistical meta-analysis to account for the intrinsic uncertainties in subsurface data and to ensure statistical significance and robustness of results. The pipeline includes model validation using e.g. likelihood ratio tests against average depletion thickness and strain thickness baselines to establish whether the models have statistically significant forecasting power. The methodology is applied to forecast seismicity for two distinctly different gas production scenarios. Results show that seismicity forecasts generated using Support Vector Machines significantly outperform beforementioned baselines. Forecasts from the method hint at decreasing seismicity rates within the next 5 years, in a conservative production scenario, and no such decrease in a higher depletion scenario, although due to the small effective sample size no statistically solid statement of this kind can be made. The presented approach can be used to make forecasts beyond the investigated 5-years period, although this requires addition of limited physics-based constraints to avoid unphysical forecasts.

We present a novel approach for the separation and recovery of Pt and Pd leached from a spent automotive catalyst relying on conventional and polymerized supported ionic liquid phases (SILPs and polySILPs, respectively). A variety of parameters with possible effects on the separation behavior, namely, acidity and concentration of the platinum group metal (PGM) containing solution, as well as different SILP and polySILP loadings, were evaluated for the separation of PGMs in the presence of high concentrations of Al, Fe, Zn, and Ce. The polySILP material demonstrated the ability to separate the PGMs from major accompanying interferences in a single separation step, while problems arising from ionic liquid leaching in the case of SILPs could be avoided. Moreover, the use of supported ionic liquid phases allowed the drastic reduction of the amount of required ionic liquid compared to conventional liquid–liquid separation, while avoiding problems arising from emulsion formation. Subsequent stripping experiments lead to further purification of the PGMs and finally desorption from the solid material into a pure solution. Eventually, the concept of chemisorbed polySILPs provides a new and convenient approach for the recycling of platinum group metals., Supported ionic liquid technology presents an environmentally benign alternative for fast and simple recovery and separation of platinum group metals from end-of-life car catalysts, thereby, contributing to a sustainable future.

Both cerium oxide (CeOx) nanoparticles and mefenamic acid (MFA) are known anti-inflammatory agents with hepatoprotective properties and are therefore prescribed for one of the major diseases in the world, nonalcoholic fatty liver disease (NAFLD). To study the potential cytotoxicity and anti-inflammatory effects as well as drug retention of a potential therapeutic CeOx/MFA supramolecular complex, a well-standardized hepatic (HepG2) spheroid model was used. Results showed that the highest cytotoxicity for the CeOx/MFA supramolecular complex was found at 50 μg/mL, while effective doses of 0.1 and 1 μg/mL yielded a significant decrease of TNF-α and IL-8 secretion. Time-resolved analysis of HepG2 spheroids revealed a spatiotemporal distribution of the supramolecular complex and limited clearance from the internal microtissue over a period of 8 days in cultivation. In summary, our results point at rapid uptake, distribution, and biostability of the supramolecular complex within the HepG2 liver spheroid model as well as a significant anti-inflammatory response at noncytotoxic levels.

Hydraulic fracturing is a key driver of well productivity and field development planning, in addition to being the most significant portion of capex in shales. Recent breakthroughs in connectivity and digital technologies have enabled the monitoring and analyses of frac operations in real-time. However, most of the digitalization effort to date has been focused on increasing operational efficiency to reduce cost. Without an equal consideration for creating effective fracture geometries, this may lead to poor resource recovery and leave significant value behind. In this paper, we - 1) demonstrate the need to balance between optimizing fracture efficiency and effectiveness; 2) present an integrated system for frac optimization using real-time, historical data along with organizational knowledge; and 3) discuss the challenges of setting up such a system and key considerations, along with examples of large, untapped potential that can be unlocked with data science to deliver real value. Currently, several service providers exist to stream frac data with interactive analytics dashboards. While they offer some customizability, most do not provide a true frac optimization platform that goes beyond frac monitoring and analytics geared towards efficiency and cost indicators. We are still dependent on an individual operator's experience and rules of thumb to make job decisions during a frac stage. In this paper, a real-time optimization workflow is presented that uses advanced data science and statistical techniques to interpret and predict time-series treatment data, integrate historical and contextual information, and honor basin-specific knowledge that has been gathered and tested over the years. Examples are presented from diagnostic pads that highlight the need for balancing stimulation effectiveness with efficiency. We demonstrate a platform to host and execute an ensemble of models and visualizations that communicate actionable insights to an operator within minutes of identifying an event, gather feedback, and learn. Results from field testing show that our system accelerates the learning curve, enables consistent decision making by operators, and can generate significant cost savings. Finally, we share learnings from our digitalization journey. Completion and stimulation expenses account for approximately half of an unconventional well cost. Automated decision making for real-time fracture treatment is the holy grail of digital completions in shales. However, a blind pursuit of efficiency may lead to sub-par fracture treatments and significant value erosion for shale assets. We present an integrated framework that connects real-time data and organizational knowledge to guide an operator to pump the best frac stage while reacting to formation response within a set of constraints. To the best of our knowledge, this is the first paper to describe the general architecture and demonstrate the viability of such a system that relies only on standard wellhead measurements during fracturing.

Consumers increasingly demand companies to take a stand on controversial socio-political debates, but the consequences of engaging in such controversies remain insufficiently documented. This research shows that controversy in brands leads to both increased offensiveness and decreased authenticity, both linked to decreased purchase intention. Political orientation moderated perceptions of authenticity in controversial brands: When participants on the political right agreed with the controversy, they perceived the controversial brand as more authentic. On the left, agreement with the controversy ledto decreased authenticity. Additionally, splitting countries into collectivist vs. individualistic societies partly explained the differing perceptions of offensiveness in controversial brands.

This work presents a multisensor hyperspectral approach for the characterization of ultramarine blue, a valuable historical pigment, at the microscopic scale combining the information of four analytical techniques at the elemental and molecular levels. The hyperspectral images collected were combined in a single hypercube, where the pixels of the various spectral components are aligned on top of each other. Selected spectral descriptors have been defined to reduce data dimensionality before applying unsupervised chemometric data analysis approaches. Lazurite, responsible for the blue color of the pigment, was detected as the major mineral phase present in synthetic and good quality pigments. Impurities like pyrite were detected in lower quality samples, although the clear identification of other mineral phases with silicate basis was more difficult. There is no correlation between the spatial distribution of the bands arising in the Raman spectra of natural samples in the region 1200–1850 cm−1 and any of the transition metals or rare earth elements (REE). With this information, the previous hypothesis (based on bulk analysis) attributing these bands to luminescence emissions due to impurities of these elements must be revised. We propose the consideration of CO2 molecules trapped in the cages of the aluminosilicate structure of sodalite-type. Additionally, correlation between certain Raman features and the combined presence of Ca, P, and REE, in particular Nd, was detected for the lowest quality pigment. Our results highlight the usefulness of fusing chemical images obtained via different imaging techniques to obtain relevant information on chemical structure and properties.

Li7La3Zr2O12 (LLZO) garnets are highly attractive to be used as solid electrolyte in solid-state Li batteries. However, LLZO suffers from chemical interaction with air and humidity, causing Li+/H+ exchange with detrimental implication on its performance, processing and scalability. To better understand the kinetics of the detrimental Li+/H+ exchange and its dependence on microstructural features, accelerated Li+/H+ exchange experiments were performed on single crystalline and polycrystalline LLZO, exposed for 80 minutes to 80 °C hot water. The resulting chemical changes were quantified by analytical methods, i.e. inductively coupled plasma optical emission spectroscopy (ICP-OES) and laser induced breakdown spectroscopy (LIBS). From the time dependence of the Li+ enrichment in the water, measured by ICP-OES, a bulk interdiffusion coefficient of Li+/H+ could be determined (7 × 10−17 m2 s−1 at 80 °C). Depth dependent concentrations were obtained from the LIBS data for both ions after establishing a calibration method enabling not only Li+ but also H+ quantification in the solid electrolyte. Short interdiffusion lengths in the 1 μm range are found for the single crystalline Ga:LLZO, in accordance with the measured bulk diffusion coefficient. In polycrystalline Ta:LLZO, however, very long diffusion tails in the 20 μm range and ion exchange fractions up to about 70% are observed. Those are attributed to fast ion interdiffusion along grain boundaries. The severe compositional changes also strongly affect the electrical properties measured by impedance spectroscopy. This study highlights that microstructural effects may be decisive for the Li+/H+ ion exchange kinetics of LLZO.

Li7La3Zr2O12 (LLZO) garnets are highly attractive to be used as solid electrolyte in solid-state Li batteries. However, LLZO suffers from chemical interaction with air and humidity, causing Li+/H+ exchange with detrimental implication on its performance, processing and scalability. To better understand the kinetics of the detrimental Li+/H+ exchange and its dependence on microstructural features, accelerated Li+/H+ exchange experiments were performed on single crystalline and polycrystalline LLZO, exposed for 80 minutes to 80 °C hot water. The resulting chemical changes were quantified by analytical methods, i.e. inductively coupled plasma optical emission spectroscopy (ICP-OES) and laser induced breakdown spectroscopy (LIBS). From the time dependence of the Li+ enrichment in the water, measured by ICP-OES, a bulk interdiffusion coefficient of Li+/H+ could be determined (7 × 10−17 m2 s−1 at 80 °C). Depth dependent concentrations were obtained from the LIBS data for both ions after establishing a calibration method enabling not only Li+ but also H+ quantification in the solid electrolyte. Short interdiffusion lengths in the 1 μm range are found for the single crystalline Ga:LLZO, in accordance with the measured bulk diffusion coefficient. In polycrystalline Ta:LLZO, however, very long diffusion tails in the 20 μm range and ion exchange fractions up to about 70% are observed. Those are attributed to fast ion interdiffusion along grain boundaries. The severe compositional changes also strongly affect the electrical properties measured by impedance spectroscopy. This study highlights that microstructural effects may be decisive for the Li+/H+ ion exchange kinetics of LLZO.