Deggendorf Institute of Technology

Aging processes at the anode–separator contact surface (“interface”) critically affect the lifetime and safety of lithium-ion batteries. Nevertheless, the role of the important fluorine–containing anode passivation layers (“solid electrolyte interphases”, SEI) under application-oriented conditions remains insufficiently understood. In this study, industrial lithium-ion cells with graphite anodes and NMC 811-based cathodes were subjected to long-term cycling and high charging rates. X-ray computed tomography (CT) combined with post-mortem scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), as well as ion exchange chromatography, Fourier transform infrared spectroscopy (FTIR), and depth-resolved X-ray photoelectron spectroscopy (XPS), was employed to investigate SEI composition as a function of cycling temperature and cycle number. The results demonstrate that cycling temperature has a significantly stronger impact on cell aging than the number of completed cycles. Elevated temperatures promote formation of fluorine containing phases within the SEI, in particular LiF, accompanied by very likely dendrite-induced blocking of electrolyte transport pathways at the anode–separator interface. Furthermore, the fraction of irreversible capacity associated with fluorine–containing SEI-compounds (LiF and Li x PO y F z ) was quantified, revealing a temperature-dependent contribution to interfacial degradation. These findings provide mechanistic insight into temperature-driven SEI evolution and highlight the critical role of LiF in aging processes of industrial lithium-ion batteries. • Cycling temperature has a stronger impact on aging than cycle number. • Elevated temperatures promote formation of fluorine-containing SEI. • Fluorine-containing SEI accumulates at the anode–separator interface. • Fluorine-containing SEI formation correlates with cumulative irreversible capacity rise. • Interfacial fluorine-containing SEI contributes to charge transport limitation and impedance growth.

ABSTRACT Boron nitride (BN) is considered for several applications in microelectronics, such as thermal management, optoelectronics, or as memristors. BN can be deposited with different deposition methods, but any integration in the back‐end‐of‐the‐line limits the deposition temperature to approximately 400°C. Further requirements include high crystal quality, sufficient film stability, and a high deposition rate to limit process costs. In particular, investigations into thin film stability and high deposition rates have rarely been conducted. Here, we propose reactive pulsed direct current sputtering at 250°C from a pure boron target and demonstrate the deposition process for stable nanocrystalline turbostratic BN. A substrate bias voltage between the plasma and sample reduces excess boron in the film and enhances its crystallinity. The process effectively prevents the formation of boric acid and ammonium borate hydrate. The stable BN films have a crystallite size of approximately 5 nm and an out‐of‐plane texture. Leakage current investigations demonstrate the insulating properties of the films. A high deposition rate of 81.6 nm min – 1 and the use of state‐of‐the‐art sputter hardware allow the immediate integration of sputtered BN into semiconductor device process lines.

We present MobiPhysio, a 2D video-based dataset designed to support AI-driven physiotherapy assessment and monitoring. The dataset contains 3686 segmented videos of 9 Active Range of Motion physiotherapy exercises performed by 58 male and female participants. The recordings are done under the variations in lighting, camera angles, occlusion, and jitter in order to mimic real-world conditions. Data collection occurred in two phases: first from non-expert participants at Stamford University Bangladesh, and later from expert participants at the Department of Physiotherapy and Rehabilitation, Jashore University of Science and Technology. The entire process was conducted under the guidance of certified physiotherapists. Each video is further annotated with assessment scores derived from the exercise-specific Exercise Accuracy Assessment Questionnaire (EAAQ), developed under expert guidance. This dataset would enable researchers to build and test AI-powered physiotherapy and rehabilitation systems, examine human motion, and create exercise monitoring solutions using available 2D camera devices like mobile phones without the need of external body-reliant sensors.

This study presents a comprehensive comparison of image quality between synchrotron-based and laboratory-based nano-computed tomography (nano-CT) systems, using a standardized 3D test phantom composed of monodisperse silica spheres. A round-robin approach was employed across multiple international facilities to benchmark performance across various imaging modalities and setups, including absorption and phase contrast techniques. Image quality was quantitatively assessed using three-dimensional signal-to-noise ratio (SNR3D), detection effectiveness (DE3D) and modulation transfer function (MTF3D) metrics. The results reveal that, while synchrotron-based nano-CT consistently delivers superior spatial resolution and shorter scan times, laboratory-based systems demonstrate competitive image quality at the cost of extended acquisition durations. Beyond the experimental comparison, the main contribution of this work is a standardized, open-source analysis framework that quantifies nano-CT image quality using SNR3D, DE3D and MTF3D of a specific phantom. This combination of metrics provides a reproducible basis for cross-platform benchmarking of synchrotron and laboratory nano-CT implementations and can be readily applied to future instruments.

Abstract In metal casting, creating undercuts in components requires cores, typically made from sand–binder mixtures such as environmentally friendly sodium silicate binders. For intricate geometries like cooling channels, higher binder content is used to achieve sufficient core strength. However, removing inorganic-bound high-strength sand cores mechanically without residue remains challenging, limiting cavity complexity in thin-walled aluminum parts. This research develops an alternative process chain for aluminum gravity casting, using sodium chloride (NaCl) salt without binding agents as the core material in the core shooting process. Moist salt powder is fluidized with compressed air and injected into a mold, where crystallization—controlled by moisture content and drying—yields a stable, temperature-resistant core. After casting, the water-soluble cores are removed and can be recycled, eliminating harmful emissions and worker exposure to respirable dust. This study examines the influence of core-shooting parameters and in-mold drying on the three-point flexural strength of porous salt cores. Increasing the fine-particle fraction is found to enhance strength, and complete drying is essential. Binder-free, salt-based cores provide superior surface quality and sufficient strength for gravity casting and can be removed either dry or by washout with water. Future work will focus on strengthening the cores to meet typical sand casting standards and reducing the crystallization process time.

Kurzfassung Es wird ein Bedarf an physikalisch-chemischen Daten zum Treibhauseffekt der Klimaerwärmung festgestellt, da die auf Beobachtung basierende CO 2 -T-Korrelation durch physikalisch-chemische Ergebnisse bisher nicht bestätigt worden ist. Ergebnisse zu den molaren Wärmekapazitäten der atmosphärischen Gase werden diskutiert. Der Beitrag des CO 2 zur Wärmespeicherung in der Atmosphäre erweist sich als vernachlässigbar. Die Rolle der sogenannten Treibhausgase als Transmitter und Sender zwischen der kinetischen Energie der Moleküle und der Photonenenergie im Strahlungsgleichgewicht (speziell im IR-(Infrarot)-Bereich) wird diskutiert. Bilanzen des CO 2 -Austauschs zwischen der Atmosphäre, der Pflanzenwelt und den Ozeanen im Vergleich zu den anthropogenen Emissionen werden kritisch bewertet. Der anthropogene Energiefluss ist um vier Größenordnungen kleiner als jener der täglichen Sonneneinstrahlung. Die Abtrennung und Endlagerung von CO 2 (CCS) und die Umsetzung von CO 2 mit Wasserstoff zu Synthesegas (CCU) werden aus energetischer Sicht besprochen. Das „Treibhaus Erdatmosphäre“ ist ein offenes System. Das Strahlungsgleichgewicht wird als Fließgleichgewicht betrachtet, welches nach den Regeln der irreversiblen Thermodynamik zu bewerten ist.

This paper presents the design, implementation, and experimental validation of a multi-output isolated flyback auxiliary power supply intended for controlling a bidirectional DC-DC converter. The system operates across a wide input voltage range of 9 V to 70 V, delivering three regulated outputs: 12 V, 5 V, and 3.3 V, which are essential for logic circuits, gate drivers, and communication modules. The flyback topology was selected for its galvanic isolation, safety features, and adaptability to input voltage variation. The converter was modeled, simulated using LTspice, and implemented on a two-layer PCB. Experimental results demonstrated reliable output regulation with a maximum efficiency of 65% under nominal conditions. Key performance metrics, including thermal behavior and component layout, were analyzed to assess suitability for compact, embedded power applications. The system delivers a total output power of approximately 34 W, making it a practical solution for isolated auxiliary supply in power electronic platforms.

[This corrects the article DOI: 10.1007/s41666-025-00216-6.].