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Towards Recycling of All‐Solid‐State Batteries with Argyrodite Sulfide Electrolytes: Insights into Electrolyte and Electrode Degradation in Dissolution‐Based Separation Processes
No full textAll‐solid‐state Li‐ion batteries (ASSBs) represent a promising leap forward in battery technology, rapidly advancing in development. Among the various solid electrolytes, argyrodite thiophosphates Li₆PS₅X (X=Cl, Br, I) stand out due to their high ionic conductivity, structural flexibility, and compatibility with a range of electrode materials, making them ideal candidates for efficient and scalable battery applications. However, despite significant performance advancements, the sustainability and recycling of ASSBs remain underexplored, posing a critical challenge for achieving efficient circular processes. This study investigates the dissolution‐based separation and recovery of argyrodite thiophosphate electrolytes and transition metal oxide electrode materials as a potential recycling strategy for ASSBs. A focus is set on the impact of solvent treatments on the recrystallization behavior of these electrolytes. Furthermore, the interactions between dissolved argyrodite thiophosphates and various transition metal oxide electrode materials (LiCoO₂, LiMn₂O₄, LiNi₀.₈Mn₀.₁Co₀.₁O₂, LiFePO₄ and Li₄Ti₅O₁₂) is examined to assess their influence on the functional properties of both the electrolytes and electrode materials. Structural, compositional and morphological changes are analyzed using X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, inductively coupled plasma mass spectrometry and X‐ray photoelectron spectroscopy. Our findings provide insights into the complexities of recycling ASSBs, but also highlight the potential for developing efficient, sustainable recycling processes
Superior temporal sulcus folding, functional network connectivity, and autistic-like traits in a non-clinical population
No full textBackground: Autistic-like traits (ALT) are prevalent across the general population and might be linked to some facets of a broader autism spectrum disorder (ASD) phenotype. Recent studies suggest an association of these traits with both genetic and brain structural markers in non-autistic individuals, showing similar spatial location of findings observed in ASD and thus suggesting a potential neurobiological continuum.
Methods: In this study, we first tested an association of ALTs (assessed with the AQ questionnaire) with cortical complexity, a cortical surface marker of early neurodevelopment, and then the association with disrupted functional connectivity. We analysed structural T1-weighted and resting-state functional MRI scans in 250 psychiatrically healthy individuals without a history of early developmental disorders, in a first step using the CAT12 toolbox for cortical complexity analysis and in a second step we used regional cortical complexity findings to apply the CONN toolbox for seed-based functional connectivity analysis.
Results: Our findings show a significant negative correlation of both AQ total and AQ attention switching subscores with left superior temporal sulcus (STS) cortical folding complexity, with the former being significantly correlated with STS to left lateral occipital cortex connectivity, while the latter showed significant positive correlation of STS to left inferior/middle frontal gyrus connectivity (n = 233; all p < 0.05, FWE cluster-level corrected). Additional analyses also revealed a significant correlation of AQ attention to detail subscores with STS to left lateral occipital cortex connectivity.
Limitations: Phenotyping might affect association results (e.g. choice of inventories); in addition, our study was limited to subclinical expressions of autistic-like traits.
Conclusions: Our findings provide further evidence for biological correlates of ALT even in the absence of clinical ASD, while establishing a link between structural variation of early developmental origin and functional connectivity
Novel Aspects in Pattern Formation Arise from Coupling Turing Reaction–Diffusion and Chemotaxis
No full textRecent experimental studies on primary hair follicle formation and feather bud morphogenesis indicate a coupling between Turing-type diffusion driven instability and chemotactic patterning. Inspired by these findings we develop and analyse a mathematical model that couples chemotaxis to a reaction–diffusion system exhibiting diffusion–driven (Turing) instability. While both systems, reaction–diffusion systems and chemotaxis, can independently generate spatial patterns, we were interested in how the coupling impacts the stability of the system, parameter region for patterning, pattern geometry, as well as the dynamics of pattern formation. We conduct a classical linear stability analysis for different model structures, and confirm our results by numerical analysis of the system. Our results show that the coupling generally increases the robustness of the patterning process by enlarging the pattern region in the parameter space. Concerning time scale and pattern regularity, we find that an increase in the chemosensitivity can speed up the patterning process for parameters inside and outside of the Turing space, but generally reduces spatial regularity of the pattern. Interestingly, our analysis indicates that pattern formation can also occur when neither the Turing nor the chemotaxis system can independently generate pattern. On the other hand, for some parameter settings, the coupling of the two processes can extinguish the pattern formation, rather than reinforce it. These theoretical findings can be used to corroborate the biological findings on morphogenesis and guide future experimental studies. From a mathematical point of view, this work sheds a light on coupling classical pattern formation systems from the parameter space perspective
A posteriori error estimates for wave maps into spheres
No full textWe provide a posteriori error estimates in the energy norm for temporal semi-discretisations of wave maps into spheres that are based on the angular momentum formulation. Our analysis is based on novel weak–strong stability estimates which we combine with suitable reconstructions of the numerical solution. We present time-adaptive numerical simulations based on the a posteriori error estimators for solutions involving blow-up
Dislocation-mediated and twinning-induced plasticity of CoCrFeMnNi in varying tribological loading scenarios
No full textCoarse-grained, metallic materials undergo microstructure refinement during tribological loading. This in turn results in changing tribological properties, so the microstructural evolution is a parameter which should not be underestimated while designing tribological systems. Single-trace experiments were conducted to understand the initiation of deformation mechanisms acting in various tribological systems. The main scope of this work was to investigate the influence of normal and friction forces as well as crystal orientations on the dominating deformation mechanism in a face-centred cubic concentrated solid solution. While varying the normal force is easily realised, varying friction forces were achieved by using several counter body materials paired against CoCrFeMnNi. The subsurface deformation layer was either mediated through dislocation slip or twinning, depending on the grain orientation and on the tribological system. A layer dominated by dislocation-based deformation is characterised by lattice rotation, the formation of a dislocation trace line or subgrain formation. Such behaviour is observed for tribological systems with a low friction coefficient. For systems dominated by deformation twinning, three types of twin appearance were observed: small twins interacting with the surface, large twins and grains with two active twin systems. Two different twinning mechanisms are discussed as responsible for these characteristics
Wolkenstein, Fabio (2022): Die dunkle Seite der Christdemokratie. Geschichte einer autoritären Versuchung: München: C. H. Beck. 222 Seiten. 16,95 €
No full textTitel und Untertitel machen neugierig. Welche „autoritäre Versuchung“ wird der in Wien lehrende Politikwissenschaftler Fabio Wolkenstein „der“ Christdemokratie attestieren? Und inwiefern ist sie für diese so konstitutiv, dass man sie als ihre dauerhafte, bis heute relevante „dunkle Seite“ bezeichnen kann? Der Verfasser wird sich ja, so vermutet man, kaum ausschließlich auf Historisches kaprizieren, und er wird wohl auch nicht nur die berühmte illiberale Demokratie Viktor Orbáns vorführen wollen. Dass christliche, genauer gesagt protestantische und katholische Politikvorstellungen in der ersten Hälfte des 20. Jahrhunderts vielfach, wenn auch keineswegs immer, einer „autoritären Versuchung“ erlagen, ist unstrittig. Unstrittig ist aber auch, dass die europäische Christdemokratie in der Nachkriegszeit – und erst in dieser entstanden die neuen, die früheren Konfessionsgrenzen überschreitenden politischen Sammelparteien dieses Namens – zu einer starken Stütze und treibenden Kraft demokratischer Politik und Verfassungsstaatlichkeit geworden ist, und zwar nicht nur auf nationalen Ebenen, sondern auch im Blick auf die Entwicklung der Europäischen Gemeinschaft. Was also ist die drohende „autoritäre Versuchung“ der Christdemokratie, die es dringlich macht, ihr mit einem auflagenstarken Essay zu Leibe zu rücken? Um mein Leseergebnis vorwegzunehmen: Sie wird mir nicht so recht klar, und auch der Verfasser scheint entgegen seiner Ankündigung keine klare Position zu beziehen
Großmaßstäbliche Versuche an Ankerpfählen für schwimmende Windenergieanlagen unter lateraler, zyklischer, multidirektionaler Belastung
No full textmultiRegionFoam: A Unified Multiphysics Framework for Multi-Region Coupled Continuum-Physical Problems
No full textThis paper presents a unified framework, called multiRegionFoam, for solving multiphysics problems of the multi-region coupling type within OpenFOAM (FOAM-extend). It is intended to supersede the existing solver with the same name. The design of the new framework is modular, allowing users to assemble a multiphysics problem region-by-region and coupling conditions interface-by-interface. The present approach allows users to choose between deploying either monolithic or partitioned interface coupling for each individual transport equation. The formulation of boundary conditions is generalised in the sense that their implementation is based on the mathematical jump/transmission conditions in the most general form for tensors of any rank. The present contribution focuses on the underlying mathematical model for interface coupled multiphysics problems, as well as on the software design and resulting code structure that enable a flexible and modular approach. Finally, deployment for different multi-region coupling cases is demonstrated, including conjugate heat, multiphase flows and fuel-cells. Source code: multiRegionFoam v1.1 [1], repository https://bitbucket.org/hmarschall/multiregionfoam/.
Article highlights:
• A novel multiphysics framework, called multiRegionFoam, has been developed for solving multi-region coupled problems in OpenFOAM.
• The design of the framework allows for a modular multiphysics setup with freedom of choice on the coupling strategy (partitioned vs. monolithic).
• Extension of the general transport equation by interface conditions enables a unified coupling approach
Toward consistent life cycle assessment for nutrient circularity: a framework based on avoided burden and substitution for decision-making
No full textAs essential inputs for sustaining soil fertility and food production, fertilizers are increasingly applied to meet the rising demand for agricultural outputs. Environmental concerns over energy use and resource depletion have driven efforts in the fertilizer industry toward sustainable production. Recent geopolitical tensions have also revealed supply chain vulnerabilities, making the development of alternative feedstocks for fertilizer production an urgent priority.
Waste and wastewater streams represents nutrient-rich resources suitable for producing secondary fertilizers, helping reduce discharge burdens and support resource recovery in line with circular economy (CE) principles. However, environmental benefits from a circular system are not automatically guaranteed; sustainable nutrient circularity depends on a deep understanding of the CE system dynamics and methodology in environmental assessment.
Life cycle assessment (LCA) is a standardized method for evaluating the potential environmental impacts of a product relative to a functional unit (FU). In applying LCA to circular end-of-life systems such as nutrient circularity, a significant challenge arises from multifunctionality. Substitution, commonly employed to address this issue, assigns avoided burdens to non-FU function. However, it is not the sole method to assign credits. In consequential LCA, avoided burden captures changes in environmental impacts driven by the FU. Inconsistencies in modeling avoided burden are widespread, risking greenwashing and undermining the reliability of decision-making.
This dissertation explores nutrient circularity, defined as the recycling of nutrients from waste and wastewater streams into fertilizers, and presents a consistent framework for modeling avoided burden to support robust decision-making. It consists of three sequential publications, each addressing distinct yet interconnected dimensions of the topic.
The first publication (literature review) offers a comprehensive assessment of the current state of nutrient circularity and critically examines the role of LCA in evaluating nutrient CE pathways. The literature review synthesizes existing CE pathways, encompassing direct land application, integrated processes that are commonly employed in wastewater treatment plants, and targeted nutrient recycling technologies. These CE pathways establish a basis for systematically categorizing their characteristics to support their accurate representation in LCA studies.
The second publication (literature review) deepens the methodological discussion by analyzing substitution and avoided burden, highlighting both theoretical foundations and the practical challenges involved in quantifying the substitution potential of secondary fertilizers. It identifies that although substitution is frequently used in LCA, its application often lacks coherence with other methodological choices, such as FU and system boundary, resulting in an arbitrary assignment of avoided burdens. Additionally, consensus is lacking on how to calculate the fertilizer technical substitution rate. A range of parameters, from internal product quality to external environmental and societal factors, is identified as key determinants in shaping the comparison between virgin and secondary fertilizers.
Building on identified gaps in the literature, the third paper presents a unified framework to clarify the distinction and calculation of avoided burden and substitution in LCA. It pinpoints that avoided burden reflects broader system-level effects than substitution. The stepwise framework supports scientifically rigorous LCA design in nutrient circularity by aligning functional units, system boundaries, research objectives, and modeling choices, improving consistency and reliability for decision-making. This framework also contributes a method based on plant nutrient uptake for calculating avoided burden and provides 65 technical substitution potentials across nine secondary fertilizer classes. By distinguishing product quality from environmental influences and reducing sampling bias through statistical analysis, it improves the robustness of life cycle inventory data.
A case study on phosphorus recycling in Germany illustrates the framework’s application through 14 scenarios combining three functional units, two LCA modeling approaches, and three levels of system boundaries. The study highlights the importance of product-specific LCA aligned with the proposed framework. Results show that different system boundaries yield different avoided burdens, even for the same functional unit, and that system modeling choices primarily shape how these burdens appear. Substitution potential influences results only certain scenarios, while inclusion of the use-on-land (UoL) phase notably influences toxicity indicators, offering a basis for comparing secondary and commercial fertilizer quality.
This dissertation clarifies the distinct role of avoided burden and substitution in nutrient circularity, addressing methodological ambiguities and promoting consistent application in LCA. By including various forms of avoided burden and their environmental co-benefits and co-costs, the framework helps prevent greenwashing and supports methodological rigor. Given the role of avoided burden in crediting systems, quality criteria are essential to avoid non-additional or short-term claims. The framework supports the further development and integration in harmonized LCA (e.g., Environmental Product Declaration), carbon credits, and system redesign under Safe and Sustainable by Design (SSbD). It also enhances phosphorus accounting, encouraging future research on improving the phosphorus cycle through circular economy strategies. In addition, it strengthens phosphorus flow representation in LCA, opening new avenues for further research focused on improving the phosphorus cycle through nutrient circularity
A Review of Marine Dual-Fuel Engine New Combustion Technology: Turbulent Jet-Controlled Premixed-Diffusion Multi-Mode Combustion
No full textDriven by stringent emission regulations, advanced combustion modes utilizing turbulent jet ignition technology are pivotal for enhancing the performance of marine low-speed natural gas dual-fuel engines. This review focuses on three novel combustion modes, yielding key conclusions: (1) Compared to the conventional DJCDC mode, the TJCDC mode exhibits a significantly higher swirl ratio and turbulence kinetic energy in the main chamber during initial combustion. This promotes natural gas jet development and combustion acceleration, leading to shorter ignition delay, reduced combustion duration, and a combustion center (CA50) positioned closer to the Top Dead Center (TDC), alongside higher peak cylinder pressure and a faster early heat release rate. Energetically, while TJCDC incurs higher heat transfer losses, it benefits from lower exhaust energy and irreversible exergy loss, indicating greater potential for useful work extraction, albeit with slightly higher indicated specific NOx emissions. (2) In the high-compression ratio TJCPC mode, the Liquid Pressurized Natural Gas (LPNG) injection parameters critically impact performance. Delaying the start of injection (SOI) or extending the injection duration degrades premixing uniformity and increases unburned methane (CH₄) slip, with the duration effects showing a load dependency. Optimizing both the injection timing and duration is, therefore, essential for emission control. (3) Increasing the excess air ratio delays the combustion phasing in TJCPC (longer ignition delay, extended combustion duration, and retarded CA50). However, this shift positions the heat release more optimally relative to the TDC, resulting in significantly improved indicated thermal efficiency. This work provides a theoretical foundation for optimizing high-efficiency, low-emission combustion strategies in marine dual-fuel engines