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In Germany, libraries or public training centers offer education programs for different target groups to foster digital participation. Yet, those programs often do not meet the requirements of people with intellectual disabilities, their formal caregivers or social institutions. A high degree of personal and organizational effort, lack of caregivers’ knowledge and expenditure of time materialize as barriers for caregivers in social institutions to support their clients to achieve digital lite...
Hybrid quantum registers, such as electron-nuclear spin systems, have emerged as promising hardware for implementing quantum information and computing protocols in scalable systems. Nevertheless, the coherent control of such systems still faces challenges. Particularly, the lower gyromagnetic ratios of the nuclear spins cause them to respond slowly to control fields, resulting in gate times that are generally longer than the coherence time of the electron. Here, we demonstrate a scheme for ci...
In this work we present a new approach for coupled CFD-Optics problems that consists of a combination of a Finite Element Method (FEM) based flow solver with a ray tracing based tool for optic forces that are induced by a laser. This is a setup that is mainly encountered in the field of optical traps. We combined the open-source computational fluid dynamics (CFD) package FEATFLOW with the raytracing software of the LAT-RUB with this task in mind. We benchmark and analyz...
The ongoing studies of the influence of internal defects on fatigue strength of additively manufactured metals adopted an internal crack or notch-like model at which the threshold stress intensity factor is the driving mechanism of fatigue failure. The current article highlights a shortcoming of this approach and offers an alternative based on X-ray microcomputed tomography and cyclic plasticity with a hybrid formulation of Chaboche and Armstrong–Frederick material laws. The presented tessell...
Every year, convective extreme weather events like summer storms, hail and heavy precipitation cause enormous damages to assets, values and human lives, especially in urban areas. Although highly relevant for the field and expertise of spatial planning, so far those events are addressed rather poorly; if at all. This is mainly for two reasons: for one, convective extreme events are of ubiquitous character, meaning they have unknown probability and place of occurrence, i.e. are accompanied by ...
Interactions between proteins and ligands, which are fundamental to many biochemical processes essential to life, are mostly studied at dilute buffer conditions. The effects of the highly crowded nature of biological cells and the effects of liquid-liquid phase separation inducing biomolecular droplet formation as a means of membrane-less compartmentalization have been largely neglected in protein binding studies. We investigated the binding of a small ligand (ANS) to one of the most multifun...
Cottonid is a layered material based 100% on cellulose that holds excellent material properties by being completely sustainable. The finite nature of petroleum-based resources nowadays makes these properties significant for technical applications again. To understand how Cottonid reacts to application-oriented mechanical loads and how it fails, development of microstructural damage on the surface and in the volume of Cottonid was studied using innovative in situ testing techniques for the fir...
The title compound, C22H22O2S2, 1, represents an example of an ortho-vanillin-based functionalized dithioether, which could be useful as a potential chelating ligand or bridging ligand for coordination chemistry. This dithioacetal 1 crystallizes in the orthorhombic space group Pbca. The phenyl rings of the benzyl groups and that of the vanillin unit form dihedral angles of 35.38 (6) and 79.77 (6)°, respectively. The crystal structure, recorded at 100 K, displays both weak intramolecula...
The crystal structure of the title compound, C10H13N·3H2O, a heterocyclic amine, was determined in the presence of water. The compound co-crystallizes with three water molecules in the asymmetric unit, which leads to the formation of hydrogen bonding in the crystal.
The polymeric title compound, [Cu2(C2H3N)2(C3H6S2)2](PF6)2, represents an example of a one-dimensional coordination polymer resulting from the reaction of [Cu(MeCN)4][PF6] with 1,3-dithiolane. The cationic one-dimensional ribbon consists of two copper(I) centers each ligated by one acetonitrile molecule and interconnected through two bridging 1,3-dithiolane ligands. One S-donor site of each ligand is κ1-bound to Cu, whereas the second S atom acts as a four-electron donor, bridging two ...
In der vorliegenden Arbeit wird eine ganzheitliche Methode zur Simulation der instationären Wechselwirkungen zwischen Fluidenergiemaschinen und Anlagen entwickelt. Diese umfasst eine nichtreflektierende Randbedingung für eindimensionale numerische Domains sowie eine nichtreflektierende Kopplungsbedingung zur zeitechten Zwei-Wege-Kopplung von eindimensionalen und dreidimensionalen numerischen Domains. Mithilfe der entwickelten nichtreflektierenden Rand- und Kopplungsbedingung lässt sich sowohl...
In recent years, additive manufacturing methods such as Fused Layer Modeling have been continuously improved by industry and research institutions. In many cases, the influence of process control on the mechanical component properties is being investigated. Influencing parameters include the infill and its orientation as well as patterns. Extrusion parameters such as the volume flow, which can be influenced by the speed, the line width, and the layer thickness, and the temperatures, which det...
The residual stress state of a sheet metal component manufactured by metal forming has a significant influence on the mechanical properties, and thus determines the time until the component fails, especially for dynamic loads. The origin of the resulting residual stress state of incrementally formed parts with regard to the forming mechanisms of shearing, bending, and the normal stress component is still under investigation. The relationship between the process parameters, the forming mechani...
Modern automotive systems integrate a variety of electrical and electronic components. To estimate the radiated emissions, the standard CISPR 25 describes the absorber-lined shielded enclosure (ALSE) method, which is the most important standardized field measurement method. However, it suffers from the need for a large anechoic chamber. To reduce costs and more conveniently integrate radiated emission investigations into the product design cycle, alternative methods that predict emissions wit...
Die Datenvernetzung innerhalb des Fahrzeuges hat Einfluss auf das Gewicht, das Volumen und die Komplexität des Fahrzeugkabelbaums. Mit den traditionellen Kfz-Bussystemen und der großen Vielfalt an Funktionen, die in Zukunft noch zunehmen wird, lässt sich ein Optimum hinsichtlich dieser Kriterien nur schwer erreichen. Eine mögliche Lösung könnte die Datenübertragung über das Kfz-Energiebordnetz darstellen. Die sogenannte Powerline Communication (PLC) ist eine Technologie, die die vorhandenen E...
The thesis at hand deals with the modelling of heat input and mass deposition during thermal spraying and especially with the capturing of the effective material behaviour of microstructures under consideration of inelasticity in the framework of thermo-mechanical continua. The heat input during thermal spraying is modelled by means of convective heat transfer as well as radiation in the framework of a non-linear rigid heat conductor which is implemented into a finite element programme. This ...
Das Ziel der Jahresabschlussprüfung liegt in der Abgabe eines hinreichend sicheren Urteils über die Verlässlichkeit und damit die Ordnungsmäßigkeit des Jahresabschlusses unter Beachtung des Grundsatzes der Wirtschaftlichkeit. Infolge des aus der Digitalisierung resultierenden Anstiegs der jährlichen Geschäftsvorfälle sowie der wachsenden Komplexität der IT-Systemlandschaften auf der Mandantenseite sehen sich Abschlussprüfer zunehmend einer enormen Datenflut ausgesetzt und die Erreichung diese...
The title compound, [FePt(C12H12O)(C18H15P)(C25H22P2)(CO)2]·2C7H8·CH2Cl2 or [(OC)2Fe(μ-dppm)(μ-C(=O)C(2,4,5-C6H2Me3)=CH)Pt(PPh3)], represents an example of a diphosphane-bridged heterobimetallic dimetallacyclopentenone complex resulting from a bimetallic activation of 1-ethynyl-2,4,5-trimethylbenzene and a metal-coordinated carbonyl ligand. The bridging μ2-C(=O)C(2,4,5-C6H2Me3)=CH unit (stemming from a carbon–carbon coupling reaction between CO and the terminal alkyne) forms a five-member...
The title compound, trimethyl(tetrahydrofuran-κO)aluminium(III), [Al(CH3)3(C4H8O)], is an addition product of trimethylaluminium and tetrahydrofuran (THF). Instead of a dimeric structure, which is very common for these types of compounds, a monomeric molecular structure is observed. The C—Al—C angles in the molecule are very different from the C—Al—C angles found in dimeric molecular structures, leading to a different symmetry around the AlIII atom. The reasons for these differences...