A single-phase bcc high-entropy alloy in the refractory Zr-Nb-Ti-V-Hf system

We report on the production and characterization of a high-entropy alloy in the refractory Zr-Nb-Ti-V-Hf system. Equiatomic ingots were produced by arc and levitation melting, and were subsequently homogenized by high-temperature annealing. We obtained a coarse-grained, single-phase high-entropy alloy, with a homogeneous distribution of the constituting elements. The phase is a chemically disordered solid solution, based on a bcc lattice with a lattice parameter of 0.336(5) nm.Comment: 6 pages, 4 figure

Hvordan kan det at man har AD/HD påvirke ens musikalske virke?

Masteroppgave i utøvende musikk- Universitetet i Agder 201

Industrielle Forschungsprojekte initiieren - Die Projektwerkstatt der WFS

Die Wirtschaftsförderung Sachsen GmbH (WFS) beschäftigt sich im Wirtschaftsraum Sachsen unter anderem mit Standortwerbung, Akquisition/Ansiedlung von Unternehmen, Strategie- und Branchenarbeit und der Initiierung von F&E-Kooperationen. Neben den Arbeitsinhalten der WFS stellt Dr.-Ing. Uwe Lienig die Herausforderungen der Produktion der Zukunft (insbesondere für KMU), die technologischen Kompetenzen Sachsens und das Format der 'Projektwerkstatt' vor. Letzteres ist ein Transferinstrument der WFS mit dem Ziel Kooperationsmöglichkeiten und konkrete Projektideen zu diskutieren

3D-Printed Microfluidic Perfusion System for Parallel Monitoring of Hydrogel-Embedded Cell Cultures

The use of three-dimensional (3D) cell cultures has become increasingly popular in the contexts of drug discovery, disease modelling, and tissue engineering, as they aim to replicate in vivo-like conditions. To achieve this, new hydrogels are being developed to mimic the extracellular matrix. Testing the ability of these hydrogels is crucial, and the presented 3D-printed microfluidic perfusion system offers a novel solution for the parallel cultivation and evaluation of four separate 3D cell cultures. This system enables easy microscopic monitoring of the hydrogel-embedded cells and significantly reduces the required volumes of hydrogel and cell suspension. This cultivation device is comprised of two 3D-printed parts, which provide four cell-containing hydrogel chambers and the associated perfusion medium chambers. An interfacing porous membrane ensures a defined hydrogel thickness and prevents flow-induced hydrogel detachment. Integrated microfluidic channels connect the perfusion chambers to the overall perfusion system, which can be operated in a standard CO2-incubator. A 3D-printed adapter ensures the compatibility of the cultivation device with standard imaging systems. Cultivation and cell staining experiments with hydrogel-embedded murine fibroblasts confirmed that cell morphology, viability, and growth inside this cultivation device are comparable with those observed within standard 96-well plates. Due to the high degree of customization offered by additive manufacturing, this system has great potential to be used as a customizable platform for 3D cell culture applications

3D-printed microfluidic perfusion system for parallel monitoring of hydrogel-embedded cell cultures

The use of three-dimensional (3D) cell cultures has become increasingly popular in the contexts of drug discovery, disease modelling, and tissue engineering, as they aim to replicate in vivo-like conditions. To achieve this, new hydrogels are being developed to mimic the extracellular matrix. Testing the ability of these hydrogels is crucial, and the presented 3D-printed microfluidic perfusion system offers a novel solution for the parallel cultivation and evaluation of four separate 3D cell cultures. This system enables easy microscopic monitoring of the hydrogel-embedded cells and significantly reduces the required volumes of hydrogel and cell suspension. This cultivation device is comprised of two 3D-printed parts, which provide four cell-containing hydrogel chambers and the associated perfusion medium chambers. An interfacing porous membrane ensures a defined hydrogel thickness and prevents flow-induced hydrogel detachment. Integrated microfluidic channels connect the perfusion chambers to the overall perfusion system, which can be operated in a standard CO2-incubator. A 3D-printed adapter ensures the compatibility of the cultivation device with standard imaging systems. Cultivation and cell staining experiments with hydrogel-embedded murine fibroblasts confirmed that cell morphology, viability, and growth inside this cultivation device are comparable with those observed within standard 96-well plates. Due to the high degree of customization offered by additive manufacturing, this system has great potential to be used as a customizable platform for 3D cell culture applications

Paradigm change in hydrogel sensor manufacturing: From recipe-driven to specification-driven process optimization

The volume production of industrial hydrogel sensors lacks a quality-assuring manufacturing technique for thin polymer films with reproducible properties. Overcoming this problem requires a paradigm change from the current recipe-driven manufacturing process to a specification-driven one. This requires techniques to measure quality-determining hydrogel film properties as well as tools and methods for the control and optimization of the manufacturing process. In this paper we present an approach that comprehensively addresses these issues. The influence of process parameters on the hydrogel film properties and the resulting sensor characteristics have been assessed by means of batch manufacturing tests and the application of several measurement techniques. Based on these investigations, we present novel methods and a tool for the optimization of the cross-linking process step, with the latter being crucial for the sensor sensitivity. Our approach is applicable to various sensor designs with different hydrogels. It has been successfully tested with a sensor solution for surface technology based on PVA/PAA hydrogel as sensing layer and a piezoelectric thickness shear resonator as transducer. Finally, unresolved issues regarding the measurement of hydrogel film parameters are outlined for future research

Innovationsprozesse in KMU unterstützen – Projektwerkstatt und Fördermöglichkeiten verbinden: Projektwerkstatt „Industrielle Reinigungstechnologien“, IVV Dresden, 14. März 2019

Im Wirtschaftsraum Sachsen beschäftigt sich die Wirtschaftsförderung Sachsen GmbH (WFS) unter anderem mit Standortwerbung, der Initiierung von F&E-Kooperationen, der Begleitung von Unternehmensgründungen und der Unterstützung beim Wachstum sächsischer Unternehmen. Neben den Arbeitsinhalten der WFS stellt Dr.-Ing. Uwe Lienig Produktionssysteme der Zukunft und damit einhergehende Herausforderungen (insbesondere für KMU), den Wirtschaftsstandort Sachsen und das Transferinstrument der WFS – die sog. Projektwerkstatt – vor. Mit der Projektwerkstatt werden Unternehmen beim Wissens- und Technologietransfer auf konkreter Projektebene unterstützt. Das Ziel ist die Umsetzung von Kooperationsmöglichkeiten und konkreten Projektideen

Electromagnetic actuator of a gentle pump mechanism for blood transport

The maximum operation time in blood pump applications is limited by blood damage caused by mechanical stress within the pump. To overcome this limitation, a new pumping principle is introduced. It is based on wave propagation inside a flexible tube in combination with positive displacement. The tube stimulation is generated by an electromagnetic actuator. In contrast to common roller pumps, it is possible to achieve a pumping operation without a complete tube occlusion. This ensures gentle pumping without damaging the blood cells. Our measurement of the pump curve and the trajectory of the shock head confirms the pumping operation without complete tube occlusion

Distributed evolutionary algorithms and their models: A survey of the state-of-the-art

The increasing complexity of real-world optimization problems raises new challenges to evolutionary computation. Responding to these challenges, distributed evolutionary computation has received considerable attention over the past decade. This article provides a comprehensive survey of the state-of-the-art distributed evolutionary algorithms and models, which have been classified into two groups according to their task division mechanism. Population-distributed models are presented with master-slave, island, cellular, hierarchical, and pool architectures, which parallelize an evolution task at population, individual, or operation levels. Dimension-distributed models include coevolution and multi-agent models, which focus on dimension reduction. Insights into the models, such as synchronization, homogeneity, communication, topology, speedup, advantages and disadvantages are also presented and discussed. The study of these models helps guide future development of different and/or improved algorithms. Also highlighted are recent hotspots in this area, including the cloud and MapReduce-based implementations, GPU and CUDA-based implementations, distributed evolutionary multiobjective optimization, and real-world applications. Further, a number of future research directions have been discussed, with a conclusion that the development of distributed evolutionary computation will continue to flourish