Netzsch (Germany)

Abstract 0.2 M Low Concentration Electrolytes (LCEs) for lithium‐based batteries formed from lithium salts with very weakly coordinating anions, i.e., the aluminate Li[Al{OC(CF 3 ) 3 } 4 ] and the gallate Li[Ga(C 2 F 5 ) 4 ] in ortho ‐difluorobenzene ( o ‐DFB), showed competitive conductivity to classical electrolytes of up to 5.0 mS cm −1 at 25 °C combined with electrochemical stability at least up to 4.5 V vs. Li/Li + . Given that a stoichiometric amount of 2 equivalents dimethoxyethane (DME) per lithium ion (as Li + complexing agent) and 2 wt.% fluoroethylene carbonate (as solid electrolyte interphase (SEI) former) were present in the LCEs, half and full‐cell measurements confirmed stable LCE cycling over 300 cycles in Lithium‐Ion‐Batteries. Even at high currents (5C), the discharge retained two thirds of the practical 1C capacities of NMC622. By contrast, a LCE made from 0.2 M LiPF 6 in EC/EMC 3:7 solution already led at a 2C rate to cell death, while a simple switch of the conducting salt to 0.2 M Li[Al{OC(CF 3 ) 3 } 4 ] led to stable cycling including rate tests for over 300 cycles and approached closely the values of the standard 1.0 M LiPF 6 electrolyte in EC/EMC 3:7 – attributed to the anions’ stability. The performance of the aluminate LCE was further evaluated in symmetrical Li‐Li cells and Lithium‐Metal‐Batteries containing 48 µm thin Lithium‐Metal‐Anodes (LMAs): LCEs improved the cell's lifetime by a factor of 3–6 at a current density of 1 mA cm −2 . Scanning electron microscope/energy‐dispersive X‐ray and potentiostatic electrochemical impedance spectroscopy measurements confirmed the exceptional stabilization of the LMAs by the aluminate LCE throughout the cycling, especially when combined with an artificial, adaptive and self‐healing SEI based on Li[PO 2 (OCH 2 CF 3 ) 2 ]. The solvation structure of standard and LCEs was investigated by NMR spectroscopic diffusion measurements and quantum chemical calculations. A three‐to‐fourfold increased Li ion mobility was found in LCEs compared to the system with 0.2 M LiPF 6 in standard carbonate solution. The presence of stable and compact Li(DME) 2 + structures as moving ions was shown and the relevance of Li + ions solvated with fluoro‐ethylene carbonate or o ‐DFB for SEI‐formation is discussed.

Abstract Ceramic/polymer composites can be chemically stable, mechanically strong, and flexible, which make them candidates for electric devices, such as pressure or temperature sensors, energy storage or harvesting devices, actuators, and so forth. Depending on the application, various electrical properties are of importance. Polymers usually have low dielectric permittivity, but increased dielectric permittivity can be achieved by the addition of the ceramic fillers with high dielectric constant. With the aim to enhance dielectric properties of the composite without loss of flexibility, 5 wt% of BaTiO3‐Fe2O3 powder was added into a polyvinylidene fluoride matrix. The powder was prepared by different synthesis conditions to produce core/shell structures. The effect of the phase composition and morphology of the BaTiO3‐Fe2O3 core/shell filler on the structure and lattice dynamics of the polymer composites was investigated. Based on the results of the thermal analysis, various parameters of ceramic/polymer composites were determined. Differences in the phase composition and morphology of the filler have an influence on the formation of various polyvinylidene fluoride allomorphs and the degree of crystallinity. Furthermore, the dielectric performances of pure polyvinylidene fluoride and the polymer/ceramic composites were measured.

Microalgae represent a promising feedstock for sustainable biomass and energy. The low cell concentration after cultivation, however, limits the current application fields. Magnetic microalgae harvesting is a recent approach to overcome the economic limitations of exploiting this natural resource. Accordingly, different particle types have been applied, mainly synthetically produced magnetic nanoparticles, though none on an industrial scale. Particle sizes between a few micrometers and a few nanometers have not been tested. We expected 200–500 nm to be advantageous for harvesting and as a compromise between the highly available surface and good separation properties. However, this intermediate magnetite particle size between the micro- and nano-scale cannot be reached via chemical synthesis. Therefore, we ground natural magnetite ore in a planetary ball mill and an agitator bead mill producing particles in the targeted size range. Applying ore particles ground from ~6 µm to 250 nm yields harvesting efficiencies comparable to synthetically produced nanoparticles (Ø ~ 10 nm), with only half the BET surface. Complete harvesting of saline microalgae Microchloropsis salina is possible with ground particles at alkaline pH. We demonstrate the feasibility of a harvesting process with natural, low-cost, easily separable, and readily available magnetite ore particles as a promising step towards exploiting valuable microalgal products in life sciences.

Abstract Next‐generation additive manufacturing processes based on UV‐curing acrylate photopolymers extend the barriers of functional part production by deploying rapid processing speeds, complex geometries with high resolutions, and an extended material spectrum. Many technologies introduce temperature‐dependent curing and decomposition behavior of acrylates to the list of process‐related challenges. This investigation targets a comprehensive analysis of the curing behavior and thermal stability of acrylic photopolymers by implementing analyzing techniques like thermogravimetric analysis, Fourier‐transform infrared spectroscopy, and differential scanning calorimetry. Significant parameters such as the UV intensity and the isothermal temperature are varied based on the design of experiments. Characteristic evolving gases at elevated temperatures are identified and discussed towards their relevance for the curing process. The calorimetric results demonstrate increasing reaction speeds with elevated UV intensities as well as a restricted accelerating effect of increasing temperatures. The reaction enthalpy proves to be strongly dependent on the chosen temperature. The results represent the base for the comparison of different kinetic curing models in future investigations.

Organosilsesquioxane hybrid materials are an important class of functional materials due to their tailorable functions and high thermal and optical stability. Recently, several studies showed that ...

Abstract Angesichts steigenden Umweltbewusstseins wird eine effiziente, energie‐ und ressourcenschonende Herstellung von Wellpappe angestrebt. Dies beeinflusst auch die Wahl der für die Produktion genutzten Pumpentechnik, etwa für die Förderung von Stärkeleim. So

Abstract Der Weltmarktführer und Hersteller von Verdrängerpumpen Netzsch Pumpen & Systeme lieferte im Mai 2020 aus seiner Niederlassung in Exton, USA, die 1.000.000ste Pumpe aus. Entwickelt wurde die Pumpe, eine Nemo Exzenterschneckenpumpe für Dickstoffschlamm im

In this work, a commercially available laser flash analysis (LFA) device is used for in situ precipitation monitoring in aluminium alloys by following thermal diffusivity for the first time. The LFA measurement methods and data processing are adapted to allow continuous heating experiments over a wide range of heating rates (0.001–1 K s−1). Methods for LFA temperature calibration and thermal lag correction are suggested. Results of continuous heating of Al Mn0.5Mg0.5 aluminium alloy from the as-cast state are compared to in situ differential scanning calorimetry (DSC) and ex situ transmission electron microscopy. It is shown comparing in situ LFA, and DSC substantially improves the interpretation of superimposed reactions, in particular, the precipitation and dissolution of Mn-containing dispersoids and Mg–Si-containing secondary particles.

This study presents a microindentation system which allows spatially resolved local as well as bulk viscoelastic material information to be obtained within one instrument. The microindentation method was merged with dynamic mechanical analysis (DMA) for a tungsten cone indenter. Three tungsten cone indenters were investigated: tungsten electrode, tungsten electrode + 2% lanthanum, and tungsten electrode + rare earth elements. Only the tungsten electrode + 2% lanthanum indenter showed the sinusoidal response, and its geometry remained unaffected by the repeated indentations. Complex moduli obtained from dynamic microindentation for high-density polyethylene, polybutylene terephthalate, polycarbonate, and thermoplastic polyurethane are in agreement with the literature. Additionally, by implementing a specially developed x-y-stage, this study showed that dynamic microindentation with a tungsten cone indenter was an adequate method to determine spatially resolved local viscoelastic surface properties.