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The morphology of Nafion (EW = 1000, Na+ form) in dilute solvents is investigated using small angle neutron scattering (SANS) and 19F NMR. SANS modeling indicates three types of particle morphology: (i) a well-defined cylindrical dispersion in glycerol and in ethylene glycol with different degrees of solvent penetration; (ii) a less-defined, highly solvated large particle (>200 nm) in water/isopropanol mixtures; and (iii) a random-coil conformation (true solution behavior) in N-methylpyrrolidone. These distinct morphological characteristics of Nafion are consistent with the main and side chain mobilities measured by 19F NMR.

Unconventional oil and gas from shale formations have emerged as some of the fastest growing energy resources in the United States, providing both cleaner energy to consumers and reducing the natio...

Vapor–liquid equilibria data of three poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)/water liquid crystals (LCs) with CO2 has been obtained up to 6 bar. The investigated LCs consist of 60% (EO)3(PO)50(EO)3 (Pluronic L81), 70% (EO)8(PO)47(EO)8 (Pluronic L92), and 70% L92-NH2. The maximum CO2 loading of the LCs was 5–13 g CO2/kg sample. Pure L81 and L92 displayed higher absorption of CO2 than the LCs. Rheology measurements revealed that the increasing viscosity of the samples decreases the CO2 loading. Water diffusion in the LCs was qualitatively investigated by nuclear magnetic resonance, confirming that free water and tightly bound water are present in the LCs. 2020 The Author(s). Published with license by Taylor and Francis Group, LLC This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way.

We examine the interplay between cathode catalyst layer (CL) porosity/thickness on mass transport limitations in single cell fuel cells comprised of Pt/C-based CLs fabricated via ultrasonic spray deposition onto polymer electrolyte membranes. We determine that the pore size distribution remains unchanged as CL thickness increases from 3.8 to 11.8 μm, but porosity decreases with increasing CL thickness. The decrease in porosity results in an increase in mass transport resistance for thicker CLs, but does not result in an increase in charge transfer resistance for the oxygen reduction reaction. We found that a fuel cell comprising a 7.5 μm-thick cathode CL delivers the highest performance (1 A cm−2 at 0.60 V at 80 °C in H2|Air at a relative humidity of 50% under ambient pressure). We attribute this high performance to the CL striking an optimal balance between solid and void networks, with the solid networks facilitating transport of H+/e− to the Pt electrocatalyst, and the void network ensuring adequate transport of O2 to, and H2O away from, the Pt electrocatalyst.

This study investigated the effects of rye bran and collagen addition to a Frankfurter-like sausage as partial fat replacement. Sensory descriptive analysis revealed that sausages where 6 g/100 g rye bran was added alone was associated with an undesired stored flavour in both cooked (P 2 relaxation measurements revealed that addition of collagen to the recipe resulted in an additional and distinct T 2 water population and thus different intrinsic water-protein interactions in the protein network when collagen protein was added, whereas the collagen addition did not impact the intrinsic microstructure of the sausages when examined by confocal laser scanning microscopy. Industrial relevance Collagen inclusion modified technological and sensory attributes and appears as a promising ingredient for development of fat replacement strategies in the manufacturing of processed meat.

Background and Aims The relation between chronic kidney disease and adverse cardiovascular events is well-established. It is also known that traditional risk factors of cardiovascular disease such as smoking, low-density lipoprotein (LDL) cholesterol and increased blood pressure, cannot fully explain the increased cardiovascular burden observed in patients with chronic kidney disease. In addition, patients with chronic kidney disease do not demonstrate typical clinical symptoms of cardiovascular disease. Thus, good biomarkers for identifying patients at risk and a better understanding of the pathophysiology leading to cardiovascular disease in patients with chronic kidney disease are needed. The objective of the present study was to investigate associations between plasma metabolites and prevalent cardiovascular disease, as well as subclinical cardiovascular disease measured as coronary artery calcification score (CACS), in patients with chronic kidney disease. Method More than 200 metabolic biomarkers, including subclasses of lipoproteins as well as the lipid composition of these, were quantified using nuclear magnetic resonance spectroscopy in 725 patients and 174 controls from the Copenhagen Chronic Kidney Disease Cohort, a single-centre prospective, observational study of non-dialysis patients with stage 1-5 chronic kidney disease. Associations between metabolites and prevalent cardiovascular disease and between metabolites and CACS were determined using multivariable logistic regression and linear regression, respectively. The statistical models were adjusted for traditional cardiovascular risk factors and multiple testing. CACS was determined by CT-scannning and calcium scores were subsequently divided into categories of 0 (no calcification), 1-100, 101-400 and > 400. Results When comparing metabolite concentrations in patients with controls, patients presented with the expected pattern of dyslipidaemia in CKD. We found that they had increased plasma triglyceride concentrations, mainly due to an increase in the triglyceride concentration in very low-density lipoprotein (VLDL) particles, while the concentration of cholesterol in high-density lipoprotein (HDL) particles was decreased. Overall, 85 metabolites were significantly associated with prevalent cardiovascular disease in a model adjusted for eGFR, age and sex (p < 0.001). After further adjusting for diabetes, body mass index, smoking and cholesterol-lowering medication, the significance was lost for all but six metabolites (p < 0.001). The consistent inverse associations with metabolites were primarily involved in HDL metabolism (e.g. ApoA-1, HDL-C and HDL-2). This also applied to the concentration of total lipids in large HDL particles, the concentration of phospholipids in large HDL particles and the the ratio of phospholipids to total lipids in very small VLDL particles. Of the 84 metabolites associated with prevalent cardiovascular disease, 71 were also associated with CACS in a similar pattern. Yet, in the model adjusted for all seven cardiovascular risk factors, only plasma glucose levels as well as the triglyceride content of larger LDL particles remained significant. Conclusion In this study we identified metabolites associated with prevalent cardiovascular disease and subclinical cardiovascular disease (CACS) in patients with CKD. For prevalent cardiovascular disease associations were mainly found for HDL associated metabolites, while CACS was associated with an increase in the triglyceride content of LDL particles and glucose. Further work needs to be done to establish whether these associations are merely a consequence of the cardiovascular burden or whether there is a causal relation.

Redox flow batteries based on organic active materials can provide a cost effective, biosustainable method for storing energy [4]. Quinones have been the primary focus for RFB applications with numerous reports on the properties and effect of structural modification by substitution with different functional groups [2, 3, 5]. The present study was focused on aromatic diaza compounds for RFB applications, namely pyrazine and quinoxaline. Both compounds undergo two electron transfer on the pyrazinic ring [6, 7]. Their small size and high solubility makes them attractive for flow cell application as it can maximize energy density [3]. In this work we examine the electrochemical properties as a function of pH and substitution. An initial screening using cyclic voltammetry in alkaline environment was performed on pristine pyrazine, and on pyrazine substituted with 1-4 methyl or carboxylic acid groups. The electron-donating methyl groups reduced the average redox potential about 55 mV per methyl group, while the electron-withdrawing carboxylic groups increased it. Additionally, the degree of substitution influenced the heterogeneous electron transfer kinetics significantly, with the greatest negative effect observed in the carboxylic pyrazines. Quinoxalines in the same alkaline environment featured similar results in different extend. The position of the functional group in regards to the active pyrazinic ring altered the degree of the effect, allowing for fine tuning of properties. Quinoxaline and quinoxaline-2,3-diyldimethanesulfonate (2,3-DMSQUI) were further examined in different pH under buffered and unbuffered solutions. It revealed that different processes take place depending on the availability of protons. Similar phenomena have been observed in quinone systems as well [2]. In the unbuffered solution, quinoxaline’s average potential had been stable up around pH = 11 where a slope of 44 mV/pH appeared. The cathodic and anodic potential had different slopes (25 and 63 mV/pH) indicating an uneven transfer coefficient, different rate limiting step, unequal amount of protons or a combination of the previous. The sharper voltammograms appeared in the high pH range. In contrast, cyclic voltammetry of 2,3-DMSQUI revealed high heterogeneous rate constant at pH 2-3. While at higher pH the kinetics appeared to be sluggish. The slopes of average, anodic and cathodic peak potential of quinoxaline in buffered solution were the same in the pH range of 2 to 12. Assuming that in buffered solution protons are always available, the difference of the slopes in the unbuffered case was most likely to an uneven amount of protons involved in the oxidation and reduction processes resulting from different acid dissociation constants. Moreover, in the acidic region, a peak at higher potential appeared which it has been attributed to an irreversible oxidative addition of a hydroxyl group [1]. Whereas, the same irreversible process was not present in 2,3-DMSQUI which meant substituting the 2 and 3 position hindered this degradation. No difference of 2,3-DSMQUI in buffered solution was found with its unbuffered counterpart, besides that the most reversible voltammogram appeared at a slightly more acidic environment ( pH = 4). Thus 2,3-DSMQUI is a good candidate for an acidic flow battery. Lastly, kinetic parameters determined by steady state voltammetry with rotating disk electrode. Diffusion coefficient and heterogeneous rate constant for quinoxaline were 7.93(±0.06)∗10-6 cm2/s and 9.6∗10-5 cm/s respectively, and 2,3-DSMQUI are 4.02(±0.06)∗10-6 cm2/s and 10.8∗10-4 cm/s. [1] M. Aleksic, J. Pantic, and V. Kapetanovic. Evaluation of kinetic parameters and redox mechanism of quinoxaline at glassy carbon electrode. Facta universitatis - series: Physics, Chemistry and Technology, 12(1):55–63, 2014. [2] C. Costentin. Electrochemical approach to the mechanistic study of proton-coupled electron transfer. Chemical Reviews, 108:2145–2179, 2008. [3] Y. Ding, C. Zhang, L. Zhang, Y. Zhou, and G. Yu. Molecular engineering of organic electroactive materials for redox flow batteries. Chemical Society Reviews, 47(1):69–103, 2018. [4] J. D. Hofmann, S. Schmalisch, S. Schwan, L. Hong, H. A. Wegner, D. Mollenhauer, J. Janek and D. Schröder. Tailoring Dihydroxyphthalazines to Enable Their Stable and Efficient Use in the Catholyte of Aqueous Redox Flow Batteries. Chemistry of Materials, 2020. [5] Y. Ji, M. A. Goulet, D. A. Pollack, D. G. Kwabi, S. Jin, D. De Porcellinis, E. F. Kerr, R. G. Gordon, and M. J. Aziz. A Phosphonate-Functionalized Quinone Redox Flow Battery at Near-Neutral pH with Record Capacity Retention Rate. Advanced Energy Materials, 9(12):1–7, 2019. [6] J. D. Milshtein, L. Su, C. Liou, A. F. Badel, and F. R. Brushett. Voltammetry study of quinoxaline in aqueous electrolytes. Electrochimica Acta,180:695–704, 2015. [7] E. D. Moorhead and D. Britton. Evidence for the Reversible Stepwise Polarographic Reduction of Pyrazine from Strong Acid Media. Analytical Letters, 1 (9):541–549, jan 1968.

Using a two-bottle choice test of short duration, we determined taste preference thresholds for eight substances tasting sweet to humans in three chimpanzees (Pan troglodytes) and four black-handed spider monkeys (Ateles geoffroyi). We found that the chimpanzees significantly preferred concentrations as low as 100-500 mM galactose, 250 mM sorbitol, 0.5-2 mM acesulfame K, 0.5-2.5 mM alitame, 0.5 mM aspartame, 0.2-2 mM sodium saccharin, 0.001-0.2 mM thaumatin, and 0.0025-0.005 mM monellin over tap water. The spider monkeys displayed lower taste preference threshold values, and thus a higher sensitivity than the chimpanzees, with five of the eight substances (2-20 mM galactose, 20-50 mM sorbitol, 0.2-1 mM acesulfame K, 0.002-0.005 mM alitame, and 0.002-0.5 mM sodium saccharin), but were generally unable to perceive the sweetness of the remaining three substances (aspartame, thaumatin, and monellin). The ranking order of sweetening potency of the eight taste substances used here correlates significantly between chimpanzees and humans, but not between spider monkeys and humans. This is in line with genetic findings reporting a higher degree of sequence identity in the Tas1r2 and the Tas1r3 genes coding for the mammalian heterodimer sweet-taste receptor between chimpanzees and humans compared to spider monkeys and humans. Taken together, the findings of the present study support the notion that taste responsiveness for substances tasting sweet to humans may correlate positively with phylogenetic relatedness. At the same time, they are also consistent with the notion that co-evolution between fruit-bearing plants and the sense of taste in animals that serve as their seed dispersers may explain between-species differences in sweet-taste perception.

By 2050, shale gas production is expected to exceed three-quarters of total US natural gas production. However, current unconventional hydrocarbon gas recovery rates are only around 20%. Maximizing production of this natural resource thus necessitates improved understanding of the fundamental mechanisms underlying hydrocarbon retention within the nanoporous shale matrix. In this study, we integrated molecular simulation with high-pressure small-angle neutron scattering (SANS), an experimental technique uniquely capable of characterizing methane behavior in situ within shale nanopores at elevated pressures. Samples were created using Marcellus shale, a gas-generative formation comprising the largest natural gas field in the United States. Our results demonstrate that, contrary to the conventional wisdom that elevated drawdown pressure increases methane recovery, a higher peak pressure led to the trapping of dense, liquid-like methane in sub-2 nm radius nanopores, which comprise more than 90% of the measured nanopore volume, due to irreversible deformation of the kerogen matrix. These findings have critical implications for pressure management strategies to maximize hydrocarbon recovery, as well as broad implications for fluid behavior under confinement. Liquid-like methane could be trapped in pores of less than 2 nm, rather than recovered, when higher peak pressure is applied during shale gas drilling. This was revealed by integrated molecular simulations and high-pressure small-angle neutron scattering on Marcellus Shale samples.

A tert-butyl protected phenol is covalently link to a mixed self-assembled monolayer on a gold or platinum electrode. The phenol reduction potential shows the expected pH-dependence of a one-electron, one-proton couple with a decrease in formal reduction potential of 59 ± 5 mV per pH. A titration of the phenol is observed with a pKa of 13.2 and the reduction potential for the phenolate is 0.11 V. NHE. The kinetic behavior of the proton-coupled oxidation deviates substantially from the commonly used models for a step-wise reaction that assume the proton transfer reactions are in equilibrium throughout the reaction. A novel model for step-wise proton-coupled reactions is presented that fully accounts for the pH dependent kinetics and allows the formal rate constants and the transfer coefficients to be determined.

Using a two-bottle choice test of short duration, we determined taste preference thresholds for sucrose, fructose, glucose, lactose, and maltose in three Western chimpanzees (Pan troglodytes verus). Further, we assessed relative preferences for these five saccharides when presented at equimolar concentrations and determined taste preference difference thresholds for sucrose, that is, the smallest concentration difference at which the chimpanzees display a preference for one of the two options. We found that the chimpanzees significantly preferred concentrations as low as 20 mM sucrose, 40 mM fructose, and 80 mM glucose, lactose, and maltose over tap water. When given a choice between all binary combinations of these five saccharides presented at equimolar concentrations of 100, 200, and 400 mM, respectively, the animals displayed significant preferences for individual saccharides in the following order: sucrose > fructose > glucose = maltose = lactose. The taste difference threshold for sucrose, expressed as Weber ratio (ΔI/I), was 0.3 and 0.4, respectively, at reference concentrations of 100 and 200 mM. The taste sensitivity of the chimpanzees to the five saccharides falls into the same range found in other primate species. Remarkably, their taste preference thresholds are similar, and with two saccharides even identical, to human taste detection thresholds. The pattern of relative taste preferences displayed by the chimpanzees was similar to that found in platyrrhine primates and to the pattern of relative sweetness as reported by humans. Taken together, the results of the present study are in line with the notion that taste sensitivity for food-associated carbohydrates may correlate positively with phylogenetic relatedness. Further, they support the notion that relative preferences for food-associated carbohydrates, but not taste difference thresholds, may correlate with dietary specialization in primates.

Clinical and preclinical studies suggest that some of the behavioral alterations observed in schizophrenia (SZ) may be mechanistically linked to synaptic dysfunction of glutamatergic signaling. Recent genetic and proteomic studies suggest alterations of cortical glutamate receptors of the AMPA-type (AMPARs), which are the predominant ligand-gated ionic channels of fast transmission at excitatory synapses. The impact of gene and protein alterations on the electrophysiological activity of AMPARs is not known in SZ. In this proof of principle work, using human postmortem brain synaptic membranes isolated from the dorsolateral prefrontal cortex (DLPFC), we combined electrophysiological analysis from microtransplanted synaptic membranes (MSM) with transcriptomic (RNA-Seq) and label-free proteomics data in 10 control and 10 subjects diagnosed with SZ. We observed in SZ a reduction in the amplitude of AMPARs currents elicited by kainate, an agonist of AMPARs that blocks the desensitization of the receptor. This reduction was not associated with protein abundance but with a reduction in kainate’s potency to activate AMPARs. Electrophysiologically-anchored dataset analysis (EDA) was used to identify synaptosomal proteins that linearly correlate with the amplitude of the AMPARs responses, gene ontology functional annotations were then used to determine protein-protein interactions. Protein modules associated with positive AMPARs current increases were down-regulated in SZ, while protein modules that were up-regulated in SZ were associated with decreased AMPARs currents. Our results indicate that transcriptomic and proteomic alterations, frequently observed in the DLPFC in SZ, converge at the synaptic level producing a functional electrophysiological impairment of AMPARs.

Interactions between a catalyst and electrolyte have paramount importance for the performance of electrochemical devices. Here, we present the cation-hydroxide-water coadsorption on the Pt surface by a rotating disk electrode and neutron reflectometry. The rotating disk electrode experiments show that the current density of Pt rapidly dropped at hydrogen oxidation potentials due to tetramethylammonium hydroxide (TMAOH)-water coadsorption. Subsequent neutron reflectometry in 0.1 M TMAOD/D

Background Activated microglia play an essential role in inflammatory responses elicited in the central nervous system (CNS). Microglia-derived extracellular vesicles (EVs) are suggested to be involved in propagation of inflammatory signals and in the modulation of cell-to-cell communication. However, there is a lack of knowledge on the regulation of EVs and how this in turn facilitates the communication between cells in the brain. Here, we characterized microglial EVs under inflammatory conditions and investigated the effects of inflammation on the EV size, quantity, and protein content. Methods We have utilized western blot, nanoparticle tracking analysis (NTA), and mass spectrometry to characterize EVs and examine the alterations of secreted EVs from a microglial cell line (BV2) following lipopolysaccharide (LPS) and tumor necrosis factor (TNF) inhibitor (etanercept) treatments, or either alone. The inflammatory responses were measured with multiplex cytokine ELISA and western blot. We also subjected TNF knockout mice to experimental stroke (permanent middle cerebral artery occlusion) and validated the effect of TNF inhibition on EV release. Results Our analysis of EVs originating from activated BV2 microglia revealed a significant increase in the intravesicular levels of TNF and interleukin (IL)-6. We also observed that the number of EVs released was reduced both in vitro and in vivo when inflammation was inhibited via the TNF pathway. Finally, via mass spectrometry, we identified 49 unique proteins in EVs released from LPS-activated microglia compared to control EVs (58 proteins in EVs released from LPS-activated microglia and 37 from control EVs). According to Gene Ontology (GO) analysis, we found a large increase of proteins related to translation and transcription in EVs from LPS. Importantly, we showed a distinct profile of proteins found in EVs released from LPS treated cells compared to control. Conclusions We demonstrate altered EV production in BV2 microglial cells and altered cytokine levels and protein composition carried by EVs in response to LPS challenge. Our findings provide new insights into the potential roles of EVs that could be related to the pathogenesis in neuroinflammatory diseases. Electronic supplementary material The online version of this article (10.1186/s12974-018-1204-7) contains supplementary material, which is available to authorized users.

Reduction of CO2 to CO and O2 in the solid oxide electrolysis cell (SOEC) has the potential to play a crucial role in closing the CO2 loop. Carbon deposition in nickel-based cells is however fatal and must be considered during CO2 electrolysis. Here, the effect of operating parameters is investigated systematically using simple current-potential experiments. Due to variations of local conditions, it is shown that higher current density and lower fuel electrode porosity will cause local carbon formation at the electrochemical reaction sites despite operating with a CO outlet concentration outside the thermodynamic carbon formation region. Attempts at mitigating the issue by coating the composite nickel/yttria-stabilized zirconia electrode with carbon-inhibiting nanoparticles and by sulfur passivation proved unsuccessful. Increasing the fuel electrode porosity is shown to mitigate the problem, but only to a certain extent. This work shows that a typical SOEC stack converting CO2 to CO and O2 is limited to as little as 15–45% conversion due to risk of carbon formation. Furthermore, cells operated in CO2-electrolysis mode are poisoned by reactant gases containing ppb-levels of sulfur, in contrast to ppm-levels for operation in fuel cell mode.

An adaptation of the Schwickerath crack initiation test (ISO 9693) was used to determine the bonding strength between an anode support and three different cathodes with a solid oxide fuel cell interconnect. Interfacial elemental characterization of the interfaces was carried out by SEM/EDS analysis on fracture surfaces to investigate the bonding mechanisms. SEM/EDS of fresh fractures were also performed to determine the cohesion/adhesion mechanism of bonding. Calculations of the residual stresses were determined by finite element simulation using ANSYS, based on thermo-mechanical properties of the materials obtained by measurement, calculation or literature.

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Inhibition of postsynaptic density protein-95 (PSD-95) decouples N-methyl-d-aspartate (NMDA) receptor downstream signaling and results in neuroprotection after focal cerebral ischemia. We have previously developed UCCB01-144, a potent dimeric PSD-95 inhibitor, which binds PSD-95 with high affinity and is neuroprotective in experimental stroke. Here, we investigate the selectivity, efficacy and toxicity of UCCB01-144 and compare with the monomeric drug candidate Tat-NR2B9c. Fluorescence polarization using purified proteins and pull-downs of mouse brain lysates showed that UCCB01-144 potently binds all four PSD-95-like membrane-associated guanylate kinases (MAGUKs). In addition, UCCB01-144 affected NMDA receptor signaling pathways in ischemic brain tissue. UCCB01-144 reduced infarct size in young and aged male mice at various doses when administered 30 min after permanent middle cerebral artery occlusion, but UCCB01-144 was not effective in young male mice when administered 1 h post-ischemia or in female mice. Furthermore, UCCB01-144 was neuroprotective in a transient stroke model in rats, and in contrast to Tat-NR2B9c, high dose of UCCB01-144 did not lead to significant changes in mean arterial blood pressure or heart rate. Overall, UCCB01-144 is a potent MAGUK inhibitor that reduces neurotoxic PSD-95-mediated signaling and improves neuronal survival following focal brain ischemia in rodents under various conditions and without causing cardiovascular side effects, which encourages further studies towards clinical stroke trials.

Rheological measurement of wax–oil gel breakage is highly susceptible to the phenomenon of adhesive breakage, hindering instrument-scale replication of cohesive breakage processes. Adhesive breakage measurements are notoriously irreproducible due to strongly nonaffine gel deformation. Efforts to ensure mechanical fixation give rise to spatially inhomogeneous deformation fields in the measuring geometry, particularly with respect to azimuthal and radial location. To elucidate the functional role of mechanically fixating geometries during gel breakage processes, three model solutions were prepared containing 5, 7.5, and 10 wt % macrocrystalline wax in dodecane. Rheograms were acquired in controlled deformation mode at imposed shear rates in the range of 0.1–1.0 s–1 using a vane or a cone and plate geometry. Yield stress values, nominally ascribed to primary peak height, were established based on 95% confidence intervals. Yielding trends confirm that adhesive breakage is particularly pronounced in high solid-fraction gels. A solid-fraction threshold delineates cohesive breakage in low solid-fraction gels from inherent adhesive breakage in high solid-fraction gels. Mechanical fixation in a vane geometry precludes wall slippage, ensuring cohesive breakage; resultant yield stress values follow a modified power-law dependency on the total wax content, characterized by a power-law exponent of ∼1.25. Nonuniform deformation within the vane geometry confers a modest (artificial) reduction in apparent yield stress value as a consequence of azimuthal integration of the torque signal. Nonuniform deformation also confers a distinct (artificial) broadening of the breakage peak and is accompanied by the appearance of a new shoulder peak located at a deformation value of ∼5. Conversely, in the cone and plate geometry, adhesive breakage occurs inherently for high solid-fraction gels and is manifested by a substantial reduction in measured yield stress, albeit without a concomitant peak broadening. Hence, the practical utility of the cone and plate geometry is limited to low solid-fraction gels that inherently exhibit cohesive breakage behavior. Mechanical fixation afforded by the vane geometry effectively precludes wall slippage, enhancing measurement reproducibility while ensuring a cohesive breakage of high solid-fraction wax-gels that otherwise rupture in adhesive mode. Locked until 22.1.2020 due to copyright restrictions. This document is the Accepted Manuscript version of a Published Work that appeared in final form in [Energy & Fuels], copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.energyfuels.8b02725

Electrochemical impedance spectroscopy, pressure change measurements, and scanning electron microscopy were used to investigate the nonaqueous Na–O2 cell potential decrease and rise (sudden deaths) on discharge and charge, respectively. To fit the impedance spectra from operating cells, an equivalent circuit model was used that takes into account the porous nature of the positive electrode and is able to distinguish between the electrolyte resistance in the pores and the charge-transfer resistance of the pore walls. The results obtained indicate that sudden death on discharge is caused by, depending on the current density, either accumulation of large NaO2 crystals that eventually block the electrode surface and/or a thin film of NaO2 forming on the cathode surface at the end of discharge, which limits charge-transfer. The commonly observed sudden rise in potential toward the end of charge may be caused by a concentration depletion of NaO2 dissolved in the electrolyte near the cathode surface and/or an ac...

The development of 3D structures exploring the properties of nano-materials and biological molecules has been shown through the years as an effective path forward for the design of advanced bio-nano architectures for enzymatic fuel cells, photo-bio energy harvesting devices, nano-biosensors and bio-actuators and other bio-nano-interfacial architectures. In this study we demonstrate a scaffold design utilizing carbon nanotubes, deoxyribose nucleic acid (DNA) and a specific DNA binding transcription factor that allows for directed immobilization of a single enzyme. Functionalized carbon nanotubes were covalently bonded to a diazonium salt modified gold surface through carbodiimide chemistry creating a brush-type nanotube alignment. The aligned nanotubes created a highly ordered structure with high surface area that allowed for the attachment of a protein assembly through a designed DNA scaffold. The enzyme immobilization was controlled by a zinc finger (ZNF) protein domain that binds to a specific dsDNA sequence. ZNF 268 was genetically fused to the small laccase (SLAC) from Streptomyces coelicolor, an enzyme belonging to the family of multi-copper oxidases, and used to demonstrate the applicability of the developed approach. Analytical techniques such as X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and enzymatic activity analysis, allowed characterization at each stage of development of the bio-nano architecture. This article is part of a Special Issue entitled Biodesign for Bioenergetics--the design and engineering of electronic transfer cofactors, proteins and protein networks, edited by Ronald L. Koder and J.L. Ross Anderson.

An Ag-Al2TiO5 composite braze was developed and successfully tested as seal for solid oxide cells. The thermo-mechanical properties of the Ag-Al2TiO5 system and the chemical compatibility between this composite braze and relevant materials used in stacks were characterized and the leak rates as a function of the operation temperature were measured. The thermal expansion coefficient in the Ag-Al2TiO5 system can be tailored by varying the amount of the ceramic filler. The brazing process can be carried out in air, the joining partners showed a good chemical stability and sufficient low leak rates were demonstrated. Furthermore, the long-term stability of the Ag-Al2TiO5 composite braze was studied under relevant SOFC and SOEC conditions. The stability of brazed Crofer/Ag-Al2TiO5/NiO-YSZ assemblies in reducing atmosphere and in pure oxygen was investigated over 500 h at 850 °C. Additionally, a cell component test was performed to investigate the durability of the Ag-Al2TiO5 seal when exposed to dual atmosphere. The seals performed well over 900 h under electrolysis operation conditions (−0.5 A cm2, 850 °C), and no cell degradation related to the Ag-Al2TiO5 sealing was found, indicating that the developed braze system is applicable for the use in SOFC/SOEC stacks.

Electrochemical reaction kinetics at the electrodes of Solid Oxide Cells (SOCs) were investigated at 700 °C for two cells with different fuel electrode microstructures as well as on a third cell with a reduced active electrode area. Three fuel mixtures were investigated – hydrogen/steam and reformate fuels hydrogen/carbon-dioxide and hydrogen/methane/steam. It was found that the kinetics at the fuel electrode were exactly the same in both reformates. The hydrogen/steam fuel displayed slightly faster kinetics than the reformate fuels. Furthermore the gas conversion impedance in the hydrogen/steam fuel split into two processes with opposing temperature behavior in the reformate fuels. An 87.5% reduction in active electrode area diminishes the gas conversion impedance in the hydrogen/steam fuel at high fuel flow rates. In both reformates, the second and third lowest frequency processes merged into a single process as the gas conversion was reduced. The SOC with finer electrode microstructure displayed improved kinetics.

Platinum electrocatalysts are active for the borohydride oxidation reaction (BOR) in an alkaline environment. However, high surface area carbon-supported platinum (Pt/C) electrodes are not viable long term in alkaline solutions at 60 °C, because Pt nanoparticles are dislodged from the C surface over time due to carbonate formation and the Pt is poisoned by intermediates in the BOR, causing a significant loss in activity. We demonstrate that platinum has increased BOR activity and durability when supported on a tantalum oxyphosphate (TaOPO4) interlayer on Vulcan carbon (VC) (Pt/[TaOPO4/VC]). Pt/[TaOPO4/VC] is compared to Pt/VC electrocatalysts at the anode of a hydrogen peroxide direct borohydride fuel cell (H2O2-DBFC) and using rotating disk electrode (RDE) voltammetry in a half cell measurements. Accelerated stress testing with rotating disk electrode voltammetry is carried out in both 0.10 M NaOH at 25 °C and 0.05 M NaBH4 + 1 M NaOH at 60 °C. The TaOPO4 interlayer between the Pt and VC improves performance and durability in the range of 10 to 20%, suggesting that this is a promising approach for stabilizing Pt in aggressive alkaline environments.

A tert-butyl protected phenol is covalently link to a mixed self-assembled monolayer on a gold or platinum electrode. The phenol reduction potential shows the expected pH-dependence of a one-electron, one-proton couple with a decrease in formal reduction potential of 59 ± 5 mV per pH. A titration of the phenol is observed with a pKa of 13.2 and the reduction potential for the phenolate is 0.11 V . NHE. The kinetic behavior of the proton-coupled oxidation deviates substantially from the commonly used models for a step-wise reaction that assume the proton transfer reactions are in equilibrium throughout the reaction. A novel model for step-wise proton-coupled reactions is presented that fully accounts for the pH dependent kinetics and allows the formal rate constants and the transfer coefficients to be determined.

Adherence to a low-gluten diet has become increasingly common in parts of the general population. However, the effects of reducing gluten-rich food items including wheat, barley and rye cereals in healthy adults are unclear. Here, we undertook a randomised, controlled, cross-over trial involving 60 middle-aged Danish adults without known disorders with two 8-week interventions comparing a low-gluten diet (2 g gluten per day) and a high-gluten diet (18 g gluten per day), separated by a washout period of at least six weeks with habitual diet (12 g gluten per day). We find that, in comparison with a high-gluten diet, a low-gluten diet induces moderate changes in the intestinal microbiome, reduces fasting and postprandial hydrogen exhalation, and leads to improvements in self-reported bloating. These observations suggest that most of the effects of a low-gluten diet in non-coeliac adults may be driven by qualitative changes in dietary fibres., Gluten-free diets are increasingly common in the general population. Here, the authors report the results of a randomised cross-over trial involving middle-aged, healthy Danish adults, showing evidence that a low-gluten diet leads to gut microbiome changes, possibly due to variations in dietary fibres.

The solid oxide cell (SOC) could play a vital role in energy storage when the share of intermittent electricity production is high. However, large-scale commercialization of the technology is still hindered by the limited lifetime. Here, we address this issue by examining the potential for repairing various failure and degradation mechanisms occurring in the fuel electrode, thereby extending the potential lifetime of a SOC system. We successfully infiltrated the nickel and yttria-stabilized zirconia cermet electrode in commercial cells with Gd-doped ceria after operation. By this method we fully reactivated the fuel electrode after simulated reactant starvation and after carbon formation. Furthermore, by infiltrating after 900 h of operation, the degradation of the fuel electrode was reduced by a factor of two over the course of 2300 h. Lastly, the scalability of the concept is demonstrated by reactivating an 8-cell stack based on a commercial design.

Forest lands hold great potential for Populus plantations, but in native boreal forests, soils normally have low pH and thus higher levels of aluminum ions (Al3+ and hydroxides). Aluminum (Al) is one of the major factors limiting plant growth on these soils by inhibiting root growth, thus reducing water and nutrient uptake and slowing growth. There is a large variation in Al resistance both among and within species. In this study, growth responses of greenhouse-grown hybrid aspen (P. tremula × tremuloides) and poplar (P. trichocarpa hybrids) were monitored in relation to changes in Al concentrations. In quartz sand, hybrid aspen was more tolerant to exogenous application of Al than P. trichocarpa hybrids. This difference in Al-tolerance was further confirmed by hematoxylin staining of the roots, with hybrid aspen displaying less staining after Al treatment than poplar clones. When planted on forest land with low pH, hybrid aspen increased growth after planting and showed low mortality. This was not the case for poplar clones; plant height decreased after planting and mortality increased. Together, our results suggest that differences in initial growth and survival on forest land among hybrid aspen and the tested poplar clones may be connected to differences in Al tolerance. Our findings that staining with hematoxylin can identify Al-tolerant Populus genotypes may help identify Al-tolerant genotypes suitable for forest land.

Local gradients within an operating solid oxide electrolyzer cell were studied using current-potential measurements and electrochemical impedance spectroscopy. The cells and operating conditions were closely related to commercial applications. The cells with fuel electrodes of nickel and yttria-stabilized zirconia (Ni-YSZ) cermets were supplied by Haldor Topsoe A/S and the operating conditions were chosen so as to take stack relevant considerations into account. Formation of carbon nanotubes in Ni containing fuel electrodes has previously been observed in co-electrolysis of H2O and CO2 [1]. Hence, the carbon formation threshold in an operating cell was investigated during electrolysis of an idealized reactant atmosphere of CO and CO2. The electrolysis current was gradually increased in steps until the cell voltage spontaneously increased, thereby indicating cell degradation and possibly the onset of carbon deposition. The outlet gas composition at each current step was estimated based on the inlet gas composition and the reactant conversion using Faraday's law. The increase in voltage was observed at lower pCO/pCO2 ratios than that corresponding to the thermodynamic threshold for carbon formation. Electrochemical impedance spectroscopy in both H2/H2O and CO/CO2 revealed an increase in resistance of the fuel electrode after each CO2 electrolysis current-voltage curve, indicating possible carbon deposition. The difference in partial oxygen pressure between inlet and outlet was analyzed to verify carbon deposition. The increase in voltage is likely due to either blocking of the reaction sites by the deposited carbon, or due to the microstructural damage caused by the carbon, or a combination of these. Moreover, the current step-size and step-length was varied to investigate the time-dependence of the detection of carbon deposition. Initial results indicate that for longer current steps, carbon formation is observed at lower pCO/pCO2 ratios. This is related to the rate of carbon deposition and the averaged nature of the cell voltage measurements. Possible reasons for these observations will be discussed in detail. In an attempt to mitigate the degradation due to carbon deposition, the Ni-YSZ electrode was infiltrated with a gadolinium doped ceria (CGO) solution. Initial results indicate that the coking tolerance was not enhanced, but it is still unclear whether infiltrated cells degrade less. However, infiltrated cells display a significant performance enhancement before coking, especially under electrolysis current. The investigation thus indicated carbon formation in the Ni containing fuel electrode before the thermodynamically calculated threshold for average measurements of the cell was reached. The deviation from the average threshold was reproduced on several cells and quantified (figure 1). The observation of carbon formation on a local, microstructural level before the expected thermodynamic threshold for average measurements on the cell level, is of crucial importance when choosing operating conditions for commercial systems. The effect would be even more severe on stack level, where the gas diffusion and temperature gradients are more pronounced. Initial results of the mitigation strategy of infiltrating CGO are negative, but increased performance prior to coking was observed. [1] Y. Tao, S. D. Ebbesen, and M. B. Mogensen, “Carbon Deposition in Solid Oxide Cells during Co-Electrolysis of H2O and CO2” Journal of the Electrochemical Society, vol. 161, pp. F337–F343, Jan. 2014. Figure 1

The influence of hydroxyl content of binders on rheological properties of screen printing inks is investigated. The actual amount of hydroxyl groups is correlated to the level of hyper-entanglement that characterizes the binders in solution. Three of the most used binders (ethyl cellulose, and two vinyl resins) were selected and characterized in solution via viscosimetry method. A high degree of hyper-entanglement was observed for ethyl cellulose polymers, whereas a mitigated effect characterized the two vinyl resins. Cerium–gadolinium oxides (CGO)-based inks, prepared using the selected binders, were investigated by means of rheology. The vinyl resin at higher hydroxyl content and low level of hyper-entanglement was demonstrated to impart superior printability properties.

The gelation behavior of Nafion dispersions was investigated using small-angle neutron scattering to better understand the mechanical toughness of dispersion-cast Nafion membranes. Three types of gelation were observed, depending on dispersing fluids: (i) homogeneous, thermally reversible gelation that was present in most aprotic polar dispersing fluids; (ii) inhomogeneous, thermally irreversible gelation as films, found in alcohols; and (iii) inhomogeneous, thermally irreversible gelation which precipitates in water/monohydric alcohol mixtures. The mechanical toughness of dispersion-cast Nafion membranes depends on the dispersing fluid, varying by more than 4 orders of magnitude. Excellent correlation between the critical gelation concentration and mechanical toughness was demonstrated with the Nafion membranes cast at 140 °C. Additional thermal effects among Nafion membranes cast at 190 °C were qualitatively related to the boiling point of dispersing fluids. Little correlation between mechanical toughne...

Background For trace element measurement in human breast milk, an accurate high-throughput sample preparation method would be desirable. In this study, a quick alkali sample dilution method was systematically compared to the traditional acid digestion pretreatment for measuring 10 trace elements in 237 human breast milk samples by inductively coupled plasma mass spectrometry (ICP-MS). Methods The alkali method involved dilution of the breast milk samples with a solution consisting of 2% butanol, 0.05% EDTA, 0.05% Triton X-100 and 1% NH4OH. The mixtures were sonicated, centrifuged and analyzed by ICP-MS. Acid digestion was performed in HNO3 at 250 °C using a Milestone Ultra CLAVE II microwave digestion system. Results Overall, the alkali dilution method gave higher analytical precision compared to acid digestion while LODs and recoveries were similar between the two methods. Spearman's correlations between measured element concentrations by the two sample preparation methods were strong (rS > 0.70) for all elements, except for Ca and Cd (rS

Background Oxidative stress and inflammation exacerbate tissue damage in the brain after ischemic stroke. Dimethyl-fumarate (DMF) and its metabolite monomethyl-fumarate (MMF) are known to stimulate anti-oxidant pathways and modulate inflammatory responses. Considering these dual effects of fumarates, we examined the effect of MMF treatment after ischemic stroke in mice. Methods Permanent middle cerebral artery occlusion (pMCAO) was performed using adult, male C57BL/6 mice. Thirty minutes after pMCAO, 20 mg/kg MMF was administered intravenously. Outcomes were evaluated 6, 24 and 48 h after pMCAO. First, we examined whether a bolus of MMF was capable of changing expression of kelch-like erythroid cell-derived protein with CNC homology-associated protein 1 (Keap1) and nuclear factor erythroid 2-related factor (Nrf)2 in the infarcted brain. Next, we studied the effect of MMF on functional recovery. To explore mechanisms potentially influencing functional changes, we examined infarct volumes, edema formation, the expression of heat shock protein (Hsp)72, hydroxycarboxylic acid receptor 2 (Hcar2), and inducible nitric oxide synthase (iNOS) in the infarcted brain using real-time PCR and Western blotting. Concentrations of a panel of pro- and anti-inflammatory cytokines (IFNγ, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p70, TNF) were examined in both the infarcted brain tissue and plasma samples 6, 24 and 48 h after pMCAO using multiplex electrochemoluminiscence analysis. Results Administration of MMF increased the protein level of Nrf2 6 h after pMCAO, and improved functional outcome at 24 and 48 h after pMCAO. MMF treatment did not influence infarct size, however reduced edema volume at both 24 and 48 h after pMCAO. MMF treatment resulted in increased Hsp72 expression in the brain 6 h after pMCAO. Hcar2 mRNA levels increased significantly 24 h after pMCAO, but were not different between saline- and MMF-treated mice. MMF treatment also increased the level of the anti-inflammatory cytokine IL-10 in the brain and plasma 6 h after pMCAO, and additionally reduced the level of the pro-inflammatory cytokine IL-12p70 in the brain at 24 and 48 h after pMCAO. Conclusions A single intravenous bolus of MMF improved sensory-motor function after ischemic stroke, reduced edema formation, and increased the levels of the neuroprotective protein Hsp72 in the brain. The early increase in IL-10 and reduction in IL-12p70 in the brain combined with changes in systemic cytokine levels may also contribute to the functional recovery after pMCAO.

Bismuth oxide based materials exhibit the highest oxygen ion conductivities, making them of great interest for use in energy conversion devices such as solid oxide fuel cells. However, these materials exhibit chemical and thermal instabilities and understanding and their stabilization is an actively pursued research goal. In this study, we investigate the structural and electrical properties of erbium oxide stabilized bismuth oxide (Er 0.4 Bi 1.6 O 3 − δ ) as thin films. These are deposited by pulsed laser deposition onto several single crystal substrates (MgO, Al2O 3 and SrTiO 3 ). The films show new forms of instabilities, both upon aging treatments in air and even under conductivity measurements, with remarkable changes in the film composition and microstructure.

Optimising membrane protein production yields in Escherichia coli can be time- and resource-consuming. Here, we present a simple and effective Membrane protein Single shot amplification recipe: MemStar. This one-shot amplification recipe is based on the E. coli strain Lemo21(DE3), the PASM-5052 auto-induction medium and, contradictorily, an IPTG induction step. Using MemStar, production yields for most bacterial membrane proteins tested were improved to reach an average of 5mgL−1 per OD600 unit, which is significantly higher than yields obtained with other common production strategies. With MemStar, we have been able to obtain new structural information for several transporters, including the sodium/proton antiporter NapA.

The objective of the present work is to generate general rheological criteria to investigate high solid loading dispersions suitable for the shaping of homogeneous ceramic bodies. Systematic analysis of the rheological properties of moderately low specific surface area (SSA) Ce 0.9 Gd 0.1 O 3-δ (CGO10) dispersions was performed in rotational and oscillatory modes. The dispersant content was optimized to attain fully stabilized dispersions. A critical upper limit for the ceramic content was introduced and denoted ϕ h . It defines the limit to non-Newtonian flow and corresponds to the highest feasible volume fraction to which reproducible dispersions are achieved. The method proposed for its determination is based on the analysis of the flow index as function of the ceramic volume fraction. For the CGO dispersions formulated in this work, ϕ h was found to be around (0.34 ± 0.04). The maximum volume fraction ( ϕ m ) was also estimated and found to be (0.55 ± 0.01).

A major, unprecedented improvement in the durability of polymer electrolyte membrane fuel cells is obtained by tuning the properties of the interface between the catalyst and the ionomer by choosing the appropriate dispersing medium. While a fuel cell cathode prepared from aqueous dispersion showed 90 mV loss at 0.8 A cm(-2) after 30,000 potential cycles (0.6-1.0 V), a fuel cell cathode prepared from glycerol dispersion exhibited only 20 mV loss after 70,000 cycles. This minimum performance loss occurs even though there was an over 80% reduction of electrochemical surface area of the Pt catalyst. These findings indicate that a proper understanding and control of the catalyst-water-ionomer (three-phase) interfaces is even more important for maintaining fuel cell durability in typical electrodes than catalyst agglomeration, and this opens up a novel path for tailoring the functional properties of electrified interfaces.

Focal cerebral ischaemia has an initial phase of inflammation and tissue injury followed by a later phase of resolution and repair. Mass spectrometry imaging (desorption electrospray ionization and matrix assisted laser desorption ionization) was applied on brain sections from mice 2 h, 24 h, 5d, 7d, and 20d after permanent focal cerebral ischaemia. Within 24 h, N-acyl-phosphatidylethanolamines, lysophosphatidylcholine, and ceramide accumulated, while sphingomyelin disappeared. At the later resolution stages, bis(monoacylglycero)phosphate (BMP(22:6/22:6)), 2-arachidonoyl-glycerol, ceramide-phosphate, sphingosine-1-phosphate, lysophosphatidylserine, and cholesteryl ester appeared. At day 5 to 7, dihydroxy derivates of docosahexaenoic and docosapentaenoic acid, some of which may be pro-resolving mediators, e.g. resolvins, were found in the injured area, and BMP(22:6/22:6) co-localized with the macrophage biomarker CD11b, and probably with cholesteryl ester. Mass spectrometry imaging can visualize spatiotemporal changes in the lipidome during the progression and resolution of focal cerebral inflammation and suggests that BMP(22:6/22:6) and N-acyl-phosphatidylethanolamines can be used as biomarkers for phagocytizing macrophages/microglia cells and dead neurones, respectively.

Deletions in the 16.6 kb mitochondrial genome have been implicated in numerous disorders that often display muscular and/or neurological symptoms due to the high-energy demands of these tissues. We describe a catalogue of 4489 putative mitochondrial DNA (mtDNA) deletions, including their frequency and relative read rate, using a combinatorial approach of mitochondria-targeted PCR, next-generation sequencing, bioinformatics, post-hoc filtering, annotation, and validation steps. Our bioinformatics pipeline uses MapSplice, an RNA-seq splice junction detection algorithm, to detect and quantify mtDNA deletion breakpoints rather than mRNA splices. Analyses of 93 samples from postmortem brain and blood found (i) the 4977 bp ‘common deletion’ was neither the most frequent deletion nor the most abundant; (ii) brain contained significantly more deletions than blood; (iii) many high frequency deletions were previously reported in MitoBreak, suggesting they are present at low levels in metabolically active tissues and are not exclusive to individuals with diagnosed mitochondrial pathologies; (iv) many individual deletions (and cumulative metrics) had significant and positive correlations with age and (v) the highest deletion burdens were observed in major depressive disorder brain, at levels greater than Kearns–Sayre Syndrome muscle. Collectively, these data suggest the Splice-Break pipeline can detect and quantify mtDNA deletions at a high level of resolution.

Sulfur impurities in carbon containing fuels for solid oxide fuel cells (SOFC), e.g. natural gas and biogas, can lead to significant losses in performance due to the sulfur sensitivity of Ni/YSZ SOFC anodes. Full cells having Ni/YSZ and Ni/ScYSZ anodes have been characterized during long-term galvanostatic operation in internal reforming gas mixture (CH4/H2O/H2:30/60/10), with 2 ppm H2S exposure to the anode, at different current densities. The aim was not only to investigate the well-known initial performance drop associated with adsorbed sulfur in the Ni/stabilized-zirconia anodes, but also to focus on the long-term effect over a few hundred of hours. This work describes and correlates the observed evolution of anode performance, over hundreds of hours, with sulfur poisoning with the different operating conditions.

Small-angle neutron scattering techniques were used to study the evolution of void morphology with press- ed density of the insensitive high explosive, TATB. Samples were studied as a loose powder and as pressed pellets, ranging in density from approx. 1 to 1.804 g cm � 3 . Inter- granular voids in the loose powder were randomly ar- ranged (non-fractal) and had a surface defined mean size of 0.66 mm. Pressing was found to induce a fractal network of voids with fractally rough interfaces. The surface-defined mean void size of the pressed samples was between 0.21- 0.33 mm over the range of densities studied and was found to increase with pressed density up to 1.720 g cm � 3 ,d e- creasing thereafter. The volume fractal dimension, indica- tive of the void arrangement, mirrored the changes in the mean void size. No systematic change in the surface fractal dimension was found. Surface area analysis allowed the average TATB grain size within the pressed samples to be quantified. An initial decrease of the mean grain size fol- lowed by an increase with pressed density suggests that the TATB grains behave in a brittle fashion at low densities and ductile at higher pressed densities.

The determination of the bonding strength (BS) between solid oxide cell (SOC) electrodes and metal interconnects (IC) is of importance since it can impact the SOC lifetime. There are several methods for determining the adhesion between ceramic and metal layers at the macro-scale level, but no standard technique for such measurement is available. In this work, the BSs between an anode support (AS) and three different cathodes with a SOC interconnect were tested in three point bending test configuration. An adaptation of the Schwickerath crack initiation test (SCIT) (ISO 9693) was used to verify its applicability for the determination of bonding strength in the interfaces. The results suggest that this test is a valid method for the mechanical characterization of SOC interfaces.

Combined soft X-ray scattering and reflectometry techniques promise analysis of polymer thin film domain structure and composition without resorting to chemical modification or isotopic labeling. This work explores the capabilities of these techniques in polymer films of poly(styrene-b-methyl methacrylate) (P(S-b-MMA)). The results demonstrate that the techniques give detailed information on the domain structure of thin films using well-known modeling procedures. Discrepancies were noted between the X-ray optical parameters that are needed to best fit the reflectivity data to the model and the expected parameters. The sources of these discrepancies are discussed in terms of instrument configuration parameters, sample attributes, and, particularly, anisotropy of the chromophore parameters. The results show that fitting the soft X-ray reflectivity data is much more sensitive to these X-ray optical parameters than the soft X-ray scattering data. Nevertheless, fits to both types of data yield quantitative measures of the polymer film's lamellar morphology that are consistent with each other and with literature values. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013

A metal-supported solid oxide fuel cell design offers competitive advantages, for example reduced material costs and improved robustness. This paper reports the performance and stability of a recently developed metal-supported cell design, based on a novel cermet anode, on a 25 cm2 (1 cm2/16 cm2 active area) cell level. An electrochemical performance comparable to state-of-the-art anode-supported cells is demonstrated. Detailed electrochemical analysis allowed assignment of the overall polarization losses quantitatively to gas diffusion in the metal support, electrooxidation in the anode functional layer, oxygen reduction in the mixed ionic-electronic conducting cathode and an additional polarization process with a rather high relaxation frequency, which may be assigned to an insulating corrosion interlayer. The durability of the cells was investigated by means of galvanostatic operation for periods of up to 1000 h as well as the dynamic behavior, such as redox-, load- and thermal cycling tests. The galvanostatic stability tests indicated a fair, but significant degradation rate (∼5% decrease in cell voltage/1000 h at 650 °C and 0.25 A cm−2). Furthermore, the metal-supported cells underwent an endurance test of 100 redox cycles at 800 °C without severe degradation nor total failure.

Metal-supported solid oxide fuel cells are expected to offer several potential advantages over conventional anode (Ni-YSZ) supported cells. For example, increased resistance against mechanical and thermal stresses and a reduction in material costs. When Ni-YSZ based anodes are used in metal supported SOFC, elements from the active anode layer may inter-diffuse with the metallic support during sintering. This work illustrates how the inter-diffusion problem can be circumvented by using an alternative anode design based on porous and electronically conducting layers, into which electrocatalytically active materials are infiltrated after sintering. The paper presents the electrochemical performance and durability of the novel planar metal-supported SOFC design. The electrode performance on symmetrical cells has also been evaluated. The novel cell and anode design shows a promising performance and durability at a broad range of temperatures and is especially suitable for intermediate temperature operation at around 650 °C.