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Abstract Filamentous microorganisms are used as molecular factories in industrial biotechnology. In 2007, a new approach to improve productivity in submerged cultivation was introduced: microparticle‐enhanced cultivation (MPEC). Since then, numerous studies have investigated the influence of microparticles on the cultivation. Most studies considered MPEC a morphology engineering approach, in which altered morphology results in increased productivity. But sometimes similar morphological changes lead to decreased productivity, suggesting that this hypothesis is not a sufficient explanation for the effects of microparticles. Effects of surface chemistry on particles were paid little attention, as particles were often considered chemically‐inert and bioinert. However, metal oxide particles strongly interact with their environment. This review links morphological, physical, and chemical properties of microparticles with effects on culture broth, filamentous morphology, and molecular biology. More precisely, surface chemistry effects of metal oxide particles lead to ion leaching, adsorption of enzymes, and generation of reactive oxygen species. Therefore, microparticles interfere with gene regulation, metabolism, and activity of enzymes. To enhance the understanding of microparticle‐based morphology engineering, further interactions between particles and cells are elaborated. The presented description of phenomena occurring in MPEC eases the targeted choice of microparticles, and thus, contributes to improving the productivity of microbial cultivation technology.

In biotechnological processes, filamentous microorganisms are known for their broad product spectrum and complex cellular morphology. Product formation and cellular morphology are often closely linked, requiring a well-defined level of mechanical stress to achieve high product concentrations. Macroparticles were added to shake flask cultures of the filamentous actinomycete Lentzea aerocolonigenes to find these optimal cultivation conditions. However, there is currently no model concept for the dependence of the strength and frequency of the bead-induced stress on the process parameters. Therefore, shake flask simulations were performed for combinations of bead size, bead concentration, bead density and shaking frequency. Contact analysis showed that the highest shear stresses were caused by bead-bottom contacts. Based on this, a newly generated characteristic parameter, the stress area ratio (SAR), was defined, which relates the bead wall shear and normal stresses to the total shear area. Comparison of the SAR with previous cultivation results revealed an optimum pattern for product concentration and mean product-to-biomass related yield coefficient. Thus, this model is a suitable tool for future optimization, comparison and scaling up of shear-sensitive microorganism cultivation. Finally, the simulation results were validated using high-speed recordings of the bead motion on the bottom of the shake flask.

Melt electrowriting (MEW) is an electric‐field‐assisted fiber‐forming biofabrication strategy for the additive manufacturing (AM) of precisely defined 3D microarchitectures. MEW is based on pressure‐driven extrusion of a polymer melt pool, currently mainly implemented at laboratory scale with specialized machine technology and limited to only few materials. This precludes the accessibility of MEW to a broader user group and can become the bottleneck of MEW's technological advancement. In contrast to conventional MEW, a filament‐based approach (F‐MEW) is introduced that exploits the technological ecosystem of fused filament fabrication (FFF), a globally used transformative AM technique. In this work, a polymer filament serves as feedstock material and is melted just on demand. By upgrading existing FFF systems, MEW of polymer microfibers is enabled, as validated with polycaprolactone (PCL) and demonstrated with direct writing of thermosensitive polydioxanone (PDO). Finally, FFF and F‐MEW are hybridized in a dual‐mode AM process. This enables multiscale constructs featuring both FFF struts and one order of magnitude smaller F‐MEW microfibers. This work opens the accessibility of F‐MEW to the large FFF user group, potentially benefitting from the plethora of filaments available for FFF, while, at the same time, expanding the FFF fabrication window.

Despite the variety of solid electrolytes available, no single solid electrolyte has been found that meets all the requirements of the successor technology of lithium-ion batteries in an optimum way. However, composite hybrid electrolytes that combine the desired properties such as high ionic conductivity or stability against lithium are promising. The addition of conductive oxide fillers to sulfide solid electrolytes has been reported to increase ionic conductivity and improve stability relative to the individual electrolytes, but the influence of the mixing process to create composite electrolytes has not been investigated. Here, we investigate Li3PS4 (LPS) and Li7La3Zr2O12 (LLZO) composite electrolytes using electrochemical impedance spectroscopy and distribution of relaxation times. The distinction between sulfide bulk and grain boundary polarization processes is possible with the methods used at temperatures below 10 °C. We propose lithium transport through the space-charge layer within the sulfide electrolyte, which increases the conductivity. With increasing mixing intensities in a high-energy ball mill, we show an overlay of the enhanced lithium-ion transport with the structural change of the sulfide matrix component, which increases the ionic conductivity of LPS from 4.1 × 10−5 S cm−1 to 1.7 × 10−4 S cm−1.

Introduction: The pharmacy profession is undergoing transformational change in Ghana. The role of pharmacists has become more patient-focused with increased accountability and responsibility. Aim: This study is aimed at reporting the experiential learning on the clinical interventions made and documented at the Allied Surgical Wards of Korle-Bu Teaching Hospital (KBTH).This involves a review of patient's medical records during the Advanced Pharmacy Practice Experience (APPE) learning. One case each from Eye, Ear, Nose, Throat, (ENT) and Dental units' subspecialty were reviewed from October 7, 2019 to November 15, 2019 b y a Pharm D student. Conclusion: The student was able to make prompt clinical interventions that contributed to patient care in clinical wards assigned during her clinical clerkship.

In order to be able to recycle composite components made of polymer and metal, which are used in the automotive industry, the joints must be broken. The success of the separation is influenced by the stress and also by the joining mechanism between the polymer and the metal. Here, force-fit and form-fit connected components are produced and crushed in a rotor impact mill with two different rotors. The results show that the crushing results differ significantly for the different rotors and for the various joining processes. In short, the hammer-type rotor provides much finer and better-separated fragments and the force-fit joints enable a better separation of metal and polymers. The additional cooling of the samples also changes the result in a way, where deep cooling significantly improves the separation of the metal and the polymer. Different types of polymers also led to a different separation result with both rotors. [ABSTRACT FROM AUTHOR]

As manufacturing and assembly processes continue to require more adaptable systems for automated handling, innovative solutions for universal gripping are emerging. These grasping systems can enable the handling of wide varieties of shapes, with gripping forces varying with grasped geometries. For the efficient usage of handling systems, precise offline and online prediction models for resulting grasping forces for different objects are necessary. In previous research, a flexible vacuum-based granular gripper was developed, for which no option for predicting gripping forces is currently available. Various gripping force prediction methodologies within the current state of the art are examined and evaluated. For an assessment of grasping forces of previously untested objects for the examined gripper with limited data and low computational effort, two methodologies are proposed. An analytical, 2D-geometry-derived gripper-specific metric for geometries is compared to a methodology based on similarities of objects to a small existing dataset. The applicability and prediction quality for different object types is analyzed through validation experiments. Gripping force estimations are possible with both methodologies, with individual weaknesses towards geometric features such as air permeabilities. With further development, robust predictions of gripping forces could be achieved for a wide range of unknown object geometries with limited experimental effort.

Current research focuses on lithium-ion battery cells with a high energy density and efficient fast-charging capabilities. However, transport limitations, and, therefore, the uniform diffusion of lithium-ions across the electrode layers, remain a challenge and could lead to reduced cell performance. One approach to overcome these transport challenges is the use of subsequently produced two-layer anodes with the particle size variation of spherical graphite (x50 = 18 µm; x50 = 11 µm). Thereby, a defined pore network is created, which reduces the ionic resistance and ensuring improved fast charging capabilities. The analysis focuses on the evaluation of electrode properties and the electrochemical performance. By examining the pore size distribution of the anodes, it has been found that during the manufacturing of the two-layer anodes, carbon black and binder particles are transported into the existing microstructure of the lower layer, resulting in localized densification between the anode layers. This could also be supported by color measurements. This effect also extends to electrochemical investigations, with electrochemical impedance spectroscopy showing significantly lower ionic resistances in all two-layer anodes. Reduced ionic resistance and tortuosity near the separator due to absorption effects enhance the ion diffusion and have a direct impact on anode performance. Cell ageing analysis showed a significant capacity decrease of almost 15 mAh g −1 in the single-layer references only, in contrast to the stability of the two-layer anodes. This could also be attributed to the reduced ionic resistance and active counteraction of binder migration. In conclusion, this study highlights how subsequently produced two-layer anodes significantly shape the electrode properties and cell performance of lithium-ion batteries.

A novel water-based lithium ferro-phosphate (LFP) cathode manufacturing process characterized by a significant reduction in the amount of solvent has been developed (semi-dry). To establish and validate this new process, Polytetrafluorethylene (PTFE) is used as a binder, with a binder content of 1 wt.%, minimizing the amount of inactive material within the electrode. Extrusion screws with multiple kneading zones stress the PTFE more intensively and thus produce more and smaller fibrils. The resulting extent of fibrillation is quantified by melting enthalpy as well as mechanical electrode properties. The degree of fibrillation of the binder in an electrode is known to influence the conductive electric and ionic pathways, which in turn affect the discharge capacity. It is shown that this process provides a flexible cathode layer that achieves a specific capacitance of 155 mAh g−1 in initial cycling tests at 0.1 C. Compared to a conventionally processed LFP cathode, the discharge capacity and overall energy output are significantly increased, and the overall energy consumption decreases for the semi-dry processed LFP cathodes.

Lithium-ion batteries (LIBs) provide the largest source of electrical energy storage today. This paper covers the use of comminution processes and, thus, crushers and mills for particle breakage and dispersing, as well as classifiers for particle separation within the process chain, from the raw material to the final lithium battery cell and its recycling at end of life. First of all, the raw materials for the active material production have to be produced either by processing primary raw materials, or by recycling the spent lithium batteries. The end-of-life battery cells have to be shredded, the materials separated and then milled in order to achieve the so-called black mass, which provides a secondary material source with very valuable components. Using these materials for the synthesis of the cathode active materials, milling has to be applied in different stages. The natural graphite, increasingly used as anode material, has to be designed in mills and classifiers for achieving targeted properties. Nanosized silicon is produced by nanomilling using stirred media mills as a primary option. Conductive additives for LIBs, like carbon black, have to be dispersed in a solvent with machines like planetary mixers, extruders or stirred media mills. In the future, mechanochemical synthesis of solid electrolytes will especially require additional application of comminution processes.

Lentzeaaerocolonigenes, as an actinomycete, is a natural producer of the antibiotic and antitumoral drug rebeccamycin. Due to the filamentous cellular morphology handling in cultivations is challenging; therefore, morphology engineering techniques are mandatory to enhance productivity. One promising approach described in the literature is the addition of mineral particles in the micrometer range to precisely adjust cellular morphology and the corresponding product synthesis (microparticle-enhanced cultivation, MPEC). Glass microparticles are introduced in this study as a novel supplementation type for bioprocess intensification in filamentous organisms. Several investigations were conducted to screen for an optimal particle setup, including particle size and concentration regarding their impact and effects on enhanced productivity, microparticle incorporation behavior into the biopellets, the viability of pellets, and morphological changes. Glass microparticles (10 g·L−1) with a median diameter of 7.9 µm, for instance, induced an up to fourfold increase in product synthesis accompanied by overall enhanced viability of biomass. Furthermore, structural elucidations showed that biopellets isolated from MPEC tend to have lower hyphal density than unsupplemented control pellets. In this context, oxygen microprofiling was conducted to better understand how internal structural changes interwind with oxygen supply into the pellets. Here, the resulting oxygen profiles are of a contradictive trend of steeper oxygen consumption with increasing glass microparticle supplementation. Eventually, MPEC was combined with another promising cultivation strategy, the supplementation of soy lecithin (7.5 g·L−1), to further increase the cultivation performance. A combination of both techniques in an optimized setup resulted in a rebeccamycin concentration of 213 mg·L−1 after 10 days of cultivation, the highest value published so far for microparticle-supplemented shake flask cultivations of L. aerocolonigenes.

Progress in new sustainable technologies depends on the development of battery materials, specifically on safer, low-cost, and higher energy density batteries. One new type of materials are the halide solid electrolytes (HSEs), which have been shown to exhibit high ionic conductivity, deformability, and oxidative stability. Here, the synthesis of Li3InCl6 (LIC) HSEs by ball-milling followed by dry room annealing is investigated. Crystal structure, particle size, and ionic conductivity are analyzed using a combination of X-ray diffraction, transmission electron microscopy, and electrochemical impedance spectroscopy. Dry room annealing increases the presence of impurities in the sample but also increases the Li+ ionic conductivity up to 1.03 mS cm−1. Additional pulsed-field gradient and relaxation time NMR measurements were performed to understand the lithium diffusion in the LIC samples. Two-dimensional diffusion – T2 relaxation correlation and T2 relaxation exchange measurements showed that there are multiple unique Li atomic motion sites, which are correlated to different rates of diffusive, micrometer-scale motion. This work outlines a simple solid-state synthesis approach and a novel strategy for designing advanced materials, understanding the ionic conduction, as well as the challenges in scalable wet processing of halide-based cathode sheets for solid-state battery applications.

In the drying process of electrodes for lithium-ion batteries, the layer structure is defined and can only be influenced slightly in the subsequent process steps. An essential point in the drying process is the fixation of the binder, ensuring both the adhesive and cohesive strength of the electrode. It is known that high drying rates lead to the segregation of the binder in the direction of the coating surface, which results in reduced mechanical stability of the electrode. In a previous publication, an experimental approach was used to investigate the underlying processes that influence binder migration. These results are now used in a model-based approach to describe the binder migration using the convection–diffusion equation. The convective term originates from the shrinkage behavior of the layer during drying due to the relative movement between the active material particles and the solvent in which the binder is dissolved or dispersed; it is expected to be the cause of the binder migration. The diffusive term, representing the binder movement in the solvent, counteracts segregation. The interaction of these forces is simulated at different drying temperatures and the associated drying rates.

To gain better understanding of the safety behavior of lithium-ion batteries under mechanical stress, crush tests are performed and reported in literature and in standards. However, many of these tests are conducted without the use of a cell clamping device, whereas external pressure is applied to the cell in a battery module in applications such as in an electric vehicle. The objective of this manuscript is to determine the effect of differing external compression on the thermal runaway of battery cells. Therefore, in this study, crush tests are performed with a hemispherical punch in a battery cell test chamber on commercially available 5 Ah pouch cells in a clamping device at four different normal stresses. The results are compared to cells that are free to expand with gas evolution. It is shown that applying compression to the cells not only results in a greater reproducibility of the experiments but that it also affects the thermal runaway process itself. With decreasing clamping stresses, the reaction time of the thermal runaway is increased by up to 19%, and the mass ejection is decreased by up to 10%, which, in turn, strongly influences the measurable gas concentrations by up to 80%. Based on this, a defined clamping compression was selected to obtain comparable results for different cell formats.