Regenerated Cellulose Fiber Solar Cell

Wearable electronics and smart textiles are growing fields in the cause to integrate modern communication and computing tools into clothing instead of carrying around smart phones and tablets. Naturally, this also requires power sources to be integrated in textiles. In this paper, a proof-of-concept is presented in form of a photovoltaic cell based on a commercially available viscose fiber. This has been realized using a silver nanowire network around the viscose fiber to establish electrical contact and a photoactive coating using the standard workhorse among organic thin film solar cells, a blend of poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM). Structure and performance of single fiber devices demonstrate their feasibility and functionality. The applied materials and methods are compatible to solution processing therewith qualifying for potential roll-to-roll large-scale production

The ultrastructure of the apical organ of the Müller's larva of the tiger flatworm Prostheceraeus crozieri

The tiger flatworm Prostheceraeus crozieri (Polycladida) develops via an eight-lobed, and three-eyed planktonic Müller's larva. This larva has an apical organ, ultrastructural details of which remain elusive due to a scarcity of studies. The evolution and possible homology of the polyclad larva with other spiralian larvae is still controversial. Here, we provide ultrastructural data and three-dimensional reconstructions of the apical organ of P. crozieri. The apical organ consists of an apical tuft complex and a dorso-apical tuft complex. The apical tuft complex features a central tuft of five long cilia, which emerge from four or five individual cells that are themselves encircled by two anchor cells. The necks of six multibranched gland cells are sandwiched between ciliated tuft cell bodies and anchor cells. The proximal parts of the ciliated cell bodies are in contact with the lateral brain neuropil via gap junctions. Located dorsally of the apical tuft complex, the dorso-apical tuft complex is characterized by several long cilia of sensory neurons, these emerge from an epidermal lumen and are closely associated with several gland cells that form a crescent apically around the dorsal anchor cell, and laterally touch the brain neuropil. Such ciliated sensory neurons emerging from a ciliated lumen are reminiscent of ampullary cells of mollusc and annelid larvae; a similar cell type can be found in the hoplonemertean decidula larva. We hypothesize that the ampullary-like cells and the tuft-forming sensory cells in the apical organs of these spiralian larvae could be homologous

Fine Cellulosic Materials Produced from Chemical Pulp: the Combined Effect of Morphology and Rate of Addition on Paper Properties

International audienceAmong bio-based reinforcement additives for paper existing on the market, microfibrillated cellulose (MFC) turned out to be a promising material, showing outstanding potential in composites science. Its relevance in papermaking as a new family of paper components was suggested more recently. There remains a number of constraints limiting the promotion of their use in papermaking, mostly related to their high cost and effect on dewatering resistance. Also, contrasting results reported in the literature suggest that the effect of fibrillation rate and quantity of such cellulosic additives in a furnish on the technological paper properties needs further research. The purpose of this study is to produce and characterize different MFC-like fine fibrous materials of varying particle size and degree of fibrillation from the same batch of pulp through mechanical treatment or fractionation. The effect of the thus obtained fine fibrous materials on paper properties is evaluated with respect to their concentration within a fiber furnish. We compared: (i) a mixture of primary and secondary fines isolated from the pulp by means of a purpose-built laboratory pressure screen; (ii) MFC-like fine fibrous materials of increasingly fibrillar character obtained by refining and subsequent steps of high-pressure homogenization. The morphology of the different materials was first characterized using flow cell based and microscopic techniques. The thus obtained materials were then applied in handsheet forming in blends of different proportions to evaluate their influence on paper properties. The results of these experiments indicate that all these products lead to a substantial decrease in air permeability and to improved mechanical properties already at low concentration, independent of the type and morphological character of the added fine cellulosic material. At higher addition rates, only highly fibrillated materials allowed a further considerable increase in tensile and z-strength. These observations should help to allow a more targeted application of this new generation of materials in papermaking, depending on the desired applicatio

Comprehensive Hazard Analysis of Failing Automotive Lithium-Ion Batteries in Overtemperature Experiments

Lithium-ion batteries (LIBs) are gaining importance in the automotive sector because of the potential of electric vehicles (EVs) to reduce greenhouse gas emissions and air pollution. However, there are serious hazards resulting from failing battery cells leading to exothermic chemical reactions inside the cell, called thermal runaway (TR). Literature of quantifying the failing behavior of modern automotive high capacity cells is rare and focusing on single hazard categories such as heat generation. Thus, the aim of this study is to quantify several hazard relevant parameters of a failing currently used battery cell extracted from a modern mass-produced EV: the temperature response of the cell, the maximum reached cell surface temperature, the amount of produced vent gas, the gas venting rate, the composition of the produced gases including electrolyte vapor and the size and composition of the produced particles at TR. For this purpose, overtemperature experiments with fresh 41 Ah automotive lithium NMC/LMO—graphite pouch cells at different state-of-charge (SOC) 100%, 30% and 0% are performed. The results are valuable for firefighters, battery pack designers, cell recyclers, cell transportation and all who deal with batteries

How Cellulose Nanofibrils and Cellulose Microparticles Impact Paper Strength – A Visualization Approach

International audienc

Two identified looming detectors in the locust: Ubiquitous lateral connections among their inputs contribute to selective responses to looming objects

In locusts, two lobula giant movement detector neurons (LGMDs) act as looming object detectors. Their reproducible responses to looming and their ethological significance makes them models for single neuron computation. But there is no comprehensive picture of the neurons that connect directly to each LGMD. We used high-through-put serial block-face scanning-electron-microscopy to reconstruct the network of input-synapses onto the LGMDs over spatial scales ranging from single synapses and small circuits, up to dendritic branches and total excitatory input. Reconstructions reveal that many trans-medullary-afferents (TmAs) connect the eye with each LGMD, one TmA per facet per LGMD. But when a TmA synapses with an LGMD it also connects laterally with another TmA. These inter-TmA synapses are always reciprocal. Total excitatory input to the LGMD 1 and 2 comes from 131,000 and 186,000 synapses reaching densities of 3.1 and 2.6 synapses per μm 2 respectively. We explored the computational consequences of reciprocal synapses between each TmA and 6 others from neighbouring columns. Since any lateral interactions between LGMD inputs have always been inhibitory we may assume these reciprocal lateral connections are most likely inhibitory. Such reciprocal inhibitory synapses increased the LGMD's selectivity for looming over passing objects, particularly at the beginning of object approach.Fil: Rind, F. Claire. University of Newcastle; Reino Unido. Medical University of Graz. Institute of Cell Biology, Histology and Embryology; AustriaFil: Wernitznig, Stefan. University of Newcastle; Reino Unido. Medical University of Graz. Institute of Cell Biology, Histology and Embryology; AustriaFil: Pölt, Peter. Graz University of Technology; Austria. Graz Centre for Electron Microscopy; AustriaFil: Zankel, Armin. Graz University of Technology; Austria. Graz Centre for Electron Microscopy; AustriaFil: Gütl, Daniel. Medical University of Graz. Institute of Cell Biology, Histology and Embryology; AustriaFil: Sztarker, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Leitinger, Gerd. University of Newcastle; Reino Unido. BioTechMed Graz; Austri