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Foundational Components for B2B Data Sharing Using the Solid Protocol
No full textThis article introduces foundational components for decentralized B2B data sharing based on the Solid Protocol, emphasizing data sovereignty, security, and interoperability.
These components are: (1) Authorization App (AuthApp) -- Facilitating granular control and compliance in access granting and revocation processes; (2) Rights Delegation Proxy (RDP) -- Supporting controlled delegation of rights, enabling natural persons to act on behalf of organizations while ensuring privacy and traceability;
(3) Data Provisioning Proxy (DPP) -- Allowing seamless and secure data provisioning across organizations while masking the identity of upstream data sources to protect business interests.
The components enable the creation of end-to-end, standards-based, flexible data value chains.
We validate their applicability through a real-world financial services use case involving loan processing, which illustrates data sharing and protection challenges in B2B ecosystems
The linear-viscoelastic relaxation time spectrum tells it all for branched polymers: Modeling of nonlinear shear and elongational rheology of polystyrene pom-poms
No full textThe Role of Surface Hydroxyls in Dehydration and Dehydrogenation of Formic Acid on FeO(001)
No full textInvestigation of the molecular mechanisms of the neuronal differentiation in p2 domain in the spinal cord
No full textSustainable Fully Inkjet-Printed Humidity Sensor Based on Ionic Liquid and Hydroxypropyl Cellulose
No full textTADF Copper(I) Complexes – from Synthesis to Application in OLEDs and 3D Laser Nanoprinting
No full textIn unserer heutigen Gesellschaft sind Materialen, die in der Lage sind, mit Licht zu interagieren, unverzichtbar geworden. Unter anderem werden organische und metallorganische Materialen bereits erfolgreich in zahlreichen Gebieten angewendet, wie beispielsweise in organischen Leuchtdioden (OLEDs) oder im 3D-Laser Druck.[1-4] Um der stetig wachsenden Nachfrage nach schnelleren und effizienteren Lösungen unter Berücksichtigung ökologischer Fragen nachzukommen, ist die Entwicklung neuer Emitter-Materialien essenziell. In der vorliegenden Arbeit, wurden neue mono-, di-, und tetranukleare Kupfer(I)-Komplexe hergestellt und untersucht. Die ersten beiden Projekte konzentrierten sich auf die strukturellen und photophysikalischen Eigenschaften der Komplexe. Im ersten Projekt wurde die Koordinationschemie von 3-Pyridylphosphin (3-PyrPhos) mit verschiedenen Kupfer(I)-(pseudo)halogeniden (CuX = I, Br, Cl, CN, SCN) und Silber(I)-halogeniden untersucht. Dies führte zu einem neuartigen zweifach verbrückten Kupfer(I)-Komplex vom Typ (3-PyrPhos)4Cu2X2. Die Struktur zeigte einen außergewöhnlich hohen intramolekularen Cu···Cu Abstand, mit einer durchschnittlichen Länge von 6.238 Å. Die Kupfer(I)-Komplexe zeigten eine ungewöhnliche Anregungswellenlängen-abhängige Emission, mit Maxima im Bereich von 510 bis 570 nm. Zur genaueren Untersuchung wurden temperaturabhängige Messungen durchgeführt. Im zweiten Projekt wurden einkernige Kuper(I)-Komplexe mit Chinolin- und Isochinolin-Liganden untersucht, die mehrere Emissionsmaxima zwischen 485 nm und 635 nm mit Quanteneffizienzen bis zu 24% aufwiesen. Das dritte Projekt konzentrierte sich auf die Entwicklung, vernetzbarer Kupfer(I)-Komplexen, mit terminalen Alkin- oder Methacrylat-gruppen im Liganden, um in einer späteren autokatalysierten Klick-Reaktion oder Photopolymerisation reagieren zu können. Erhaltene zweikernige Komplexe wiesen eine hohe Löslichkeit von mehr als 20 mg/ml in mindestens einem Lösungsmittel (Toluol, Chlorbenzol, DCM) auf, was sie zu idealen Kandidaten für lösungsprozessierte OLEDs macht. Die Komplexe zeigten eine hervorragende Photolumineszenz im grün-blauen bis gelben Bereich mit Quantenausbeuten von bis zu 99%. Ausgewählte Komplexe wurden während eines Forschungsaufenthalts an der Universität Durham (UK) in lösungsgefertigten OLEDs verbaut, was zu externen Quanteneffizienzen bis zu 8,9% und Leuchtdichten bis zu ⁓5000 cd m-2 führte. Darüber hinaus wurden zweikernige Komplexe mit Methacrylat-Liganden im 3D Laser-Nanodruck mit 2-Photonen-Absorption eingesetzt, was zu hochauflösenden Strukturen führte
Automated extraction of comprehensive digital twin models for smart manufacturing systems
Full text linkManufacturing systems involve multiple, often conflicting, objectives referred to as performance indicators,
including production efficiency, resource utilization, energy consumption, carbon emissions, and waste reduc-
tion, which correspond to different dimensions of the system, such as time, energy consumption, and waste
generation aspects. Digital Twins have emerged as a powerful tool, integrating data-driven simulation and
analysis of complex systems, such as manufacturing systems. Process Mining (PM), along with data analysis,
enables the automatic discovery of executable discrete-event simulation models directly from production event
logs. These data-driven models are the key to enabling near-real-time Digital Twins of discrete-event systems.
Stochastic Petri Nets (SPNs) offer a robust and intuitive modeling formalism well-suited for representing the
extracted models derived from PM, particularly in the context of manufacturing systems. However, standard
SPNs face challenges in incorporating dimensions beyond time, such as energy consumption and waste gener-
ation. This limitation often results in suboptimal decision-making and reduced system efficiency. In this paper,
we propose a Comprehensive Digital Twin (CDT) framework that employs Multi-Flow Process Mining (MFPM) to
automatically extract Multidimensional Stochastic Petri Nets (MDSPNs) as underlying models of manufacturing
systems. To support the modeling and simulation of extracted MDSPNs, we introduce and utilize our tool,
MDPySPN. The CDT framework supports multi-objective decision-making for various performance indicators of
the system. Through an illustrative case study of hot forging process chains, we showcase the development of
CDT for time, energy consumption, and waste generation dimensions. We further illustrate the utilization of CDT
to analyze and support decision-making to enhance the case study system according to its objectives
Microstructure Simulation to Predict the Influence of Particle Properties on Permeability of Granular Porous Media
Full text linkThis work investigates the influence of particle shape and asperity height on the flow
behavior of porous granular media using computational fluid dynamics (CFD). The
developed framework includes the generation of random structured particle beds with
LIGGGHTS using the Discrete Element Method (DEM) and the subsequent analysis of the
pore space in terms of porosity and specific surface area. CFD is then applied to analyze
the flow through the pore space at a Reynolds number of Re = 1. In the post-processing,
the permeability of the granular porous media is derived and a significant influence of the
particle shape and asperity height on the permeability and porosity can be seen. In the end,
a comparative analysis of simulations results and analytical models based on Ergun and
Carman-Kozeny is conducted. The study reveals that the Carman-Kozeny approach exhib-
its a remarkable capacity to replicate the influence of particle shape and surface asperity,
while the Ergun approach demonstrates a more limited suitability
Local structure and dynamics of a Zr-based bulk metallic glass during ex situ and in situ annealing
Full text linkAdvanced transmission electron microscopy (TEM) techniques are utilized to investigate the structural evolution and underlying mechanisms driving relaxation in metallic glasses. We quantify changes in medium-range order (MRO) using fluctuation electron microscopy (FEM), while electron correlation microscopy (ECM) combined with in situ heating allows us to directly probe local dynamics with unprecedented spatial resolution. FEM analysis provides a semi-quantitative estimate of the MRO volume fraction, based on either the peak height or the peak integral of the variance. This measure was found to increase in structurally relaxed samples compared to the as-cast condition, observed across both predefined annealed states and during in situ heating. Complementary in situ analyses uncover a temperature-dependent reduction in atomic mobility. This decrease in dynamics—which aligns with the phenomenon of irreversible structural relaxation, often termed ”aging”—is examined with high spatial resolution for the first time. The findings on structural modifications and local relaxation behavior during heating are discussed in detail and compared with results obtained via other characterization methods and across different material systems, providing a comprehensive understanding of relaxation processes in metallic glasses