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The degradation of SnO2and Bi2O3based CO2converting gas-diffusion electrodes was investigated to shed light on the contribution of a possible catalyst leaching and electrode flooding onto the degradation process.

In Singapore, the use of traditional Chinese medicine (TCM) alongside Western medicine (WM) is common. There are risks of adverse herb-drug interactions when taken concurrently. Current literature suggests that TCM use is not regularly reported to WM doctors in Singapore, but the underlying reasons are not understood.

The paper focuses on the performance and aging behavior of lithium nickel cobalt manganese oxide commercial standard material (NCM-111) which is improved with a post synthesis process in order to enhance the cathode active material of lithium-ion pouch cells regarding their capacity and cyclic stability. The aging behavior of the cells is analyzed with electrochemical impedance spectroscopy (EIS) during long-term electrochemical load cycling tests based on the Common Artemis Driving Cycle (CADC). Additionally, post-mortem investigations using scanning electron microscopy (SEM) and X-ray diffraction (XRD) were performed. The results demonstrate that post-processing of electrode active material is an effective tool to improve the properties of lithium-ion electrode materials, especially regarding high energy applications and lifetime optimization. The paper bridges the gap between lithium-ion battery electrode material development and the necessary cell testing under automotive relevant conditions which is important for the evaluation of new lithium-ion battery materials for automotive applications.

The solid electrolyte interphase (SEI) is a complex and fragile passivation layer with crucial importance for the functionality of lithium-ion batteries. Due to its fragility and reactivity, the use of in situ techniques is preferable for the determination of the SEI’s true structure and morphology during its formation. In this study, we use in situ neutron reflectometry (NR) and in situ atomic force microscopy (AFM) to investigate the SEI formation on a carbon surface. It was found that a lithium-rich adsorption layer is already present at the open circuit voltage on the carbon sample surface and that the first decomposition products start to deposit close to this potential. During the negative potential sweep, the growth of the SEI can be observed in detail by AFM and NR. This allows precise monitoring of the morphology evolution and the resulting heterogeneities of individual SEI features. NR measurements show a maximum SEI thickness of 192 Å at the lower cutoff potential (0.02 V vs Li/Li+), which slightly decreases during the positive potential scan. The scattering length density (SLD) obtained by NR provides additional information on the SEI’s chemical nature and structural evolution.

Herein we report a magnesium powder anode with medium capacity retention and recovery of potential plateaus over reversible cycling. Furthermore powder anodes showed an optimized behavior during charging leading to an improved coulomb efficiency compared to magnesium foil anodes. Battery cells with a powder anode showed pronounced voltage plateaus and no problem to reach a 2.8 V cut-off voltage. Within the compaction pressure range investigated a magnesium powder anode prepared by relatively low pressures showed advantageous properties and was further investigated by electrochemical impedance spectroscopy.

In the search for post-lithium battery systems, magnesium–sulfur batteries have attracted research attention in recent years due to their high potential energy density, raw material abundance, and low cost. Despite significant progress, the system still lacks cycling stability mainly associated with the ongoing parasitic reduction of sulfur at the anode surface, resulting in the loss of active materials and passivating surface layer formation on the anode. In addition to sulfur retention approaches on the cathode side, the protection of the reductive anode surface by an artificial solid electrolyte interphase (SEI) represents a promising approach, which contrarily does not impede the sulfur cathode kinetics. In this study, an organic coating approach based on ionomers and polymers is pursued to combine the desired properties of mechanical flexibility and high ionic conductivity while enabling a facile and energy-efficient preparation. Despite exhibiting higher polarization overpotentials in Mg–Mg cells, the charge overpotential in Mg–S cells was decreased by the coated anodes with the initial Coulombic efficiency being significantly increased. Consequently, the discharge capacity after 300 cycles applying an Aquivion/PVDF-coated Mg anode was twice that of a pristine Mg anode, indicating effective polysulfide repulsion from the Mg surface by the artificial SEI. This was backed by operando imaging during long-term OCV revealing a non-colored separator, i.e. mitigated self-discharge. While SEM, AFM, IR and XPS were applied to gain further insights into the surface morphology and composition, scalable coating techniques were investigated in addition to ensure practical relevance. Remarkably therein, the Mg anode preparation and all surface coatings were prepared under ambient conditions, which facilitates future electrode and cell assembly. Overall, this study highlights the important role of Mg anode coatings to improve the electrochemical performance of magnesium–sulfur batteries.

We investigated the reduction process of sulfur during cycling in a lithium–sulfur battery, correlating the output of ultraviolet–visible (UV–vis) spectroscopy and further characterization techniques with a theoretical model. The experimental setup allows carrying out UV–vis absorption measurements under argon atmosphere. The characteristic absorption bands (λmax) of sulfur and dilithium sulfide dissolved in tetra-ethylene glycol dimethyl ether (TEGDME) are determined to be at 265 and 255 nm, respectively. Reference solutions of polysulfides diminish the λmaxin the UV region with decrease of polysulfide order. The same tendency is observed in the range between 25–75% depth of discharge (DOD), caused by a progressive reduction of polysulfides in the electrolyte. At 425 and 615 nm, absorption bands are identified in the reference polysulfide solutions and also in the electrolyte at different DOD. These bands are interpreted as the characteristic bands of S42–and S3•–, and concentration changes of these species are determined semiquantitatively. The highest concentration of polysulfides is found at around 37% DOD (450 Ah·kgS–1). This was confirmed by the results of electrochemical impedance spectroscopy and computer simulations.

For lithium-sulfur batteries, porous carbon/sulfur composite cathodes are the primary solution to compensate the non-conductive nature of sulfur. The composition and structure of this class of cathodes are crucial to the electrochemical performance, achieved energy density and the stability of the cell. Electrochemical impedance spectroscopy is employed to investigate and correlate the electrochemical performance of lithium-sulfur batteries to the composition and microstructure of differently fabricated carbon/sulfur composite cathodes. A transmission line model is applied to identify different underlying electrochemical processes appearing in the impedance response of a range of porous carbon/sulfur cathodes. The integration of a lithium ring serving as a counter electrode coupled with advanced wiring has allowed an artifact-free recording of the cathode impedance at different states of charge with the aim to investigate the evolution of impedance during discharge/charge and the kinetics of charge transfer depending on the infiltration method and the utilized carbon host. It is shown that impedance response of this class of cathodes is highly diverse and the plausible underlying processes are discussed in details. To this end, quasi-solid-state and various polysulfide-based charge transfer mechanisms are identified and their time constants are reported.

This work presents results of a measurement setup which was constructed for understanding the performance contributions of the individual compartments and reactions taking place in the patented concept of IDEAL-Cell (described in detail in[1]). By inserting a third measurement point at the central membrane of an ideal cell it was possible to measure the cell in three different modes corresponding to hydrogen, oxygen compartment and the full cell. Recorded maximum power densities of (~4, ~7, 11, 16) mW/cm2 at (600, 650, 700, 750) degC in H2-O2 atmosphere respectively were observed which were similar to the values of proof of concept ideal cell samples tested so far. Moreover in our setup it was possible to record higher maximum power densities for the hydrogen (proton conducting) compartment which was (~14, 22, 33*, ~38*) mW/cm2 at (600, 650, 700, 750) degC.

ZusammenfassungZur Charakterisierung von Brennstoffzellen und Zellkomponenten wird eine ganze Reihe von verschiedenen Messverfahren eingesetzt. Neben ex-situ-oberflächenanalytischen Charakterisierungsmethoden wie Rasterelektronenmikroskopie (REM) und Energiedispersive Röntgenspektroskopie (EDX), Porosimetrie, Röntgendiffraktometrie (XRD) Röntgenphotoelektronenspektroskopie (XPS) werden noch in-situ-elektrochemische Charakterisierungsmethoden eingesetzt. Die einfachste und daher wohl die am häufigsten verwendete elektrochemische Charakterisierungsmethode ist die Aufnahme einer Strom-Spannungskennlinie (U-i-Kennlinie), die durch elektrochemische, elektronische und ionische Leitfähigkeiten sowie bei hohen Stromdichten zunehmend auch von Diffusionstermen bestimmt wird. Eine quantitative und qualitative Trennung dieser Terme ist nicht nur von grundsätzlichem Interesse, sondern kann auch dazu beitragen, die Elektroden-Membran-Elektroden-Einheiten (MEA) und das Zelldesign gezielt zu verbessern. Die elektrochemische Impedanzspektroskopie (EIS) ist dafür besonders gut geeignet, da nach Auswertung der über einen weiten Frequenzbereich gemessenen Elektrodenimpedanz bzw. Zellimpedanz mit einem Elektrodenmodell (Ersatzschaltbild) diese Größen simultan und in einem großen Potenzialbereich bzw. Stromdichtebereich bestimmt werden können.

New binuclear complexes of threecoordinate CuIhave been synthesized with the ligand 1,2,4,5tetrakistetramethylguanidinobenzene ttmgb. Subsequent oxidation of the ligand unit was achieved by reaction with Br2or I2. Reaction with Br2leads to oxidation of both the ligand and the copper ions and formation of a bicationic dinuclear CuIIcomplex. On the other hand, oxidation with I2leads only to oxidation of the ligand during the first step. A metastable coordination polymer of laddertype structure results, in which the coordination number of the CuIions increases to four. Electrical measurements show that this polymer is semiconductive with a band gap of around 1 eV. The electronic structure of the polymer was further studied by Xray photoelectron spectroscopy XPS, Raman and VisNIR spectroscopy. It decomposes with oxidation of the copper ions in an exothermal reaction at temperatures around 230 °C. Oxidation of the copper ions and decomposition of the polymer can also be achieved by reaction of the polymer with phenanthroline.

The study of the behaviour of fuel cells by using various in-situ and ex-situ diagnostic methods is a main topic at the German Aerospace Center (DLR). The degradation of cell components of polymer electrolyte fuel cells (PEFC, DMFC) and of solid oxide fuel cells (SOFC) are of special interest. For this purpose physical and electrochemical methods are used individually as well as in combination. In addition to routinely applied electrochemical methods different methods for locally resolved current density measurements by means of segmented cell technology and integrated temperature sensors have been developed. The latest development with segmented bipolar plates based on printed circuit boards (PCB) is used both in single PEFC cells and stacks. Furthermore, a measuring system for segmented SOFC cells has been developed allowing for the spatially resolved characterisation of cells in terms of current density/voltage characteristics, impedance spectroscopy data, operating temperature and gas composition. The paper summarises the capabilities at DLR with respect to the analysis of fuel cells’ behaviour and gives examples of analytical studies to discuss the potentials and limitations of the diagnostic methodology that is applied.

A transimpedance amplifier circuit as well as an instrumental amplifier circuit were used to measure current densities of a zinc-air battery with an integrated segmented current collector foil. Error calculation showed that the transimpedance amplifier is superior to the used instrumental amplifier, but both methods provide valuable and consistent results. They both showed comparable results with operando insight into the current distribution of the battery. The knowledge about those distributions is essential to avoid fast degradation of battery materials and irreversible capacity loss due to heterogeneous dissolution of the anode during discharge. In this work we showed that oxygen starvation as well as gas flow rate leads to large current gradients. It was also demonstrated that heterogeneous current distributions on cathode side induces also a heterogenous dissolution behavior on the anode, resulting in irreversible capacity loss.

The function of α4β1 and α4β7 integrins in hematopoiesis is controversial. While some experimental evidence suggests a crucial role for these integrins in retention and expansion of progenitor cells and lymphopoiesis, others report a less important role in hematopoiesis. Using mice with a deletion of the β1 and the β7 integrin genes restricted to the hematopoietic system we show here that α4β1 and α4β7 integrins are not essential for differentiation of lymphocytes or myelocytes. However, β1β7 mutant mice displayed a transient increase of colony-forming unit (CFU-C) progenitors in the bone marrow and, after phenylhydrazine-induced anemia, a decreased number of splenic erythroid colony-forming units in culture (CFUe's). Array gene expression analysis of CD4+CD8+double-positive (DP) and CD4–CD8–double-negative (DN) thymocytes and CD19+and CD4+splenocytes did not provide any evidence for a compensatory mechanism explaining the mild phenotype. These data show that α4β1 and α4β7 are not required for blood cell differentiation, although in their absence alterations in numbers and distribution of progenitor cells were observed.

Eosinophilic inflammation is a common feature of numerous eosinophil‐associated gastrointestinal (EGID) diseases. Central to eosinophil migration into the gastrointestinal tract are the integrin‐mediated interactions with adhesion molecules. Although the mechanisms regulating eosinophil homing into the small intestine have begun to be elucidated, the adhesion pathways responsible for eosinophil trafficking into the large intestine are unknown. We investigated the role of adhesion pathways in eosinophil recruitment into the large intestine during homeostasis and disease. First, using a hapten‐induced colonic injury model, we demonstrate that in contrast to the small intestine, eosinophil recruitment into the colon is regulated by a β7‐integrin addressin cell adhesion molecule‐1‐independent pathway. Characterization of integrin expression on colonic eosinophils by flow cytometry analysis revealed that colonic CC chemokine receptor 3+eosinophils express the intercellular adhesion molecule‐1 (ICAM‐1) counter‐receptor integrins αL, αM, and β2. Using ICAM‐1‐deficient mice and anti‐ICAM‐1 neutralizing antibodies, we show that hapten‐induced colonic eosinophilic inflammation is critically dependent on ICAM‐1. These studies demonstrate that β2‐integrin/ICAM‐1‐dependent pathways are integral to eosinophil recruitment into the colon during GI inflammation associated with colonic injury.

The reaction of the α and β forms of C3S52−with thiophosgene yields two isomeric carbon sulfides α,α-C4S6and α,β-C4S6, respectively. The crystal structures of both compounds could be determined for the first time. Both structures are made up of almost planar molecules. The α,α-isomer (1,3-dithiolo-(4,5-d)-1,3-dithol-2,5-dithione) is D2h-symmetric, while the α,β-isomer is approximately Cs-symmetric. In the molecules of both isomers the two different C3S5units are retained without significant alterations of structural parameters. α,α-C4S6is unstable with respect to α,β-C4S6. The molecular rearrangement can be induced by a short thermal treatment at 150 °C. Significant differences are found in the mass spectra fragmentation patterns. Only α,β-C4S6shows an intense signal for C3S2+and is therefore a potential source for the synthesis of carbon subsulfide viaflash vacuum pyrolysis. Only α,β-C4S6forms a stable adduct with I2. α,β-C4S6·I2was already known (F. L. Lu, K. M. Keshavarz-K, G. Srdanov, R. H. Jacobson and F. Wudl, J. Org. Chem., 1989, 54, 2165, ref. 19), but a second polymorph is formed on crystallisation from a different solvent. The two polymorphic forms do not show differences in the structures of the individual molecules but show a different packing pattern. α,β-C4S6·I2is remarkably thermally stable. Thermal analysis shows that I2cleavage occurs in that temperature region above 200 °C when C–S bonds are broken and CS2and I2are simultaneously liberated. Performed at 270 °C thermolysis of α,β-C4S6·I2yields under cleavage of I2and CS2a black polymeric carbon sulfide (CS)xwhich is probably a mixture of graphitic carbon and unidentified amorphous polymeric carbon sulfides.

Bronchus-associated lymphoid tissue (BALT) participates in airway immune responses. However, little is known about the lymphocyte–endothelial adhesion cascades that recruit lymphocytes from blood into BALT. We show that high endothelial venules (HEVs) in BALT express substantial levels of VCAM-1, in marked contrast to HEVs in other secondary lymphoid tissues. BALT HEVs also express the L-selectin ligand PNAd. Anti–L-selectin, anti-PNAd, and anti–LFA-1 mAbs almost completely block the homing of B and T lymphocytes into BALT, whereas anti–α4 integrin and anti–VCAM-1 mAbs inhibit homing by nearly 40%. α4β7 integrin and MAdCAM-1 are not involved. Importantly, we found that mAbs against α4 integrin and VCAM-1 significantly block the migration of total T cells (80% memory phenotype) but not naive T and B cells to BALT. These results suggest that an adhesion cascade, which includes L-selectin/PNAd, α4β1 integrin/VCAM-1, and LFA-1, targets specific lymphocyte subsets to BALT. This high level of involvement of α4β1 integrin/VCAM-1 is unique among secondary lymphoid tissues, and may help unify lymphocyte migration pathways and immune responses in BALT and other bronchopulmonary tissues.

Prion pathogenesis following oral exposure is thought to involve gut-associated lymphatic tissue, which includes Peyer's patches (PPs) and M cells. Recruitment of activated B lymphocytes to PPs requires α4β7integrin; PPs of β7−/−mice are normal in number but are atrophic and almost entirely devoid of B cells. Here we report that minimal infectious dose and disease incubation after oral exposure to logarithmic dilutions of prion inoculum were similar in β7−/−and wild-type mice, and PPs of both β7−/−and wild-type mice contained 3–4 log LD50/g prion infectivity ≥125 days after challenge. Despite marked reduction of B cells, M cells were present in β7−/−mice. In contrast, mice deficient in both tumor necrosis factor and lymphotoxin-α (TNFα−/−× LTα−/−) or in lymphocytes (RAG-1−/−, μMT), in which numbers of PPs are reduced in number, were highly resistant to oral challenge, and their intestines were virtually devoid of prion infectivity at all times after challenge. Therefore, lymphoreticular requirements for enteric and for intraperitoneal uptake of prions differ from each other. Although susceptibility to prion infection following oral challenge correlates with the number of PPs, it is remarkably independent of the number of PP-associated lymphocytes.

7 integrins mediate homing and retention of lymphocytes to the normal and inflamed small bowel in a tissue-selective fashion. In the present study, we investigated the expression of 7 integrins after small bowel transplantation (SBT) and tested the effects of blocking 7-mediated pathways by using monoclonal antibody (mAb) or knockout mice.

Mouse mammary tumor virus (MMTV) is acquired by neonates through milk and first infects lymphocytes in Peyer's patches. We show here that newborn mice lacking β7 integrin or L-selectin were infected with MMTV at wild-type levels in both their lymphoid and mammary tissues. Superantigen-mediated activation and cognate T cell deletion were also unimpaired in both types of null mice. A large proportion of neonatal Peyer's patch lymphocytes in wild-type mice were β7 and β1 integrin low and both populations increased in response to MMTV infection. These results suggest that adhesion molecules other than β7 integrin or L-selectin play a role in lymphocyte homing in the gut, peripheral lymph nodes and mammary gland in response to MMTV infection.

Eosinophils accumulate in the gastrointestinal tract in a number of medical disorders, but the mechanisms involved are largely unknown. To understand the significance of cytokine expression by enterocytes, enterocyte transgenic mice that overexpressed the eosinophil-selective cytokines eotaxin and interleukin (IL)-5 were generated. Transgenic mice, generated by utilizing the rat intestinal fatty acid-binding protein promoter (Fabpi), overexpressed the mRNA for these cytokines in the small intestine. Overexpression of IL-5 resulted in marked increases of eosinophils in the bone marrow and blood, whereas eotaxin overexpression resulted in similar levels compared with nontransgenic control mice. In contrast, both IL-5 and eotaxin transgenic mice had significant accumulation of eosinophils in the gastrointestinal mucosa compared with control mice. Eotaxin-induced gastrointestinal eosinophilia was substantially higher than that induced by IL-5 and was especially prominent within the lamina propria of the villi. Interestingly, genetic rescue of eotaxin deficiency (by transgenic overexpression of eotaxin in eotaxin gene-targeted mice) resulted in significant restoration of gastrointestinal eosinophil levels. Finally, the intestinal eosinophilia induced by the eotaxin transgene was β7integrin-dependent. Taken together, these results demonstrate that expression of eotaxin and IL-5 in intestinal epithelium induces compartmentalized dysregulation of eosinophil trafficking and the important role of the β7integrin in gastrointestinal allergic responses.

Vascular cellular adhesion molecule (VCAM)-1 is a membrane-bound cellular adhesion molecule that mediates adhesive interactions between hematopoietic progenitor cells and stromal cells in the bone marrow (BM) and between leukocytes and endothelial as well as dendritic cells. Since VCAM-1–deficient mice die embryonically, conditional VCAM-1 mutant mice were generated to analyze the in vivo function of this adhesion molecule. Here we show that interferon-induced Cre-loxP–mediated deletion of the VCAM-1 gene after birth efficiently ablates expression of VCAM-1 in most tissues like, for example, BM, lymphoid organs, and lung, but not in brain. Induced VCAM-1 deficiency leads to a reduction of immature B cells in the BM and to an increase of these cells in peripheral blood but not in lymphoid organs. Mature recirculating B cells are reduced in the BM. In a migration assay, the number of mature B cells that appears in the BM after intravenous injection is decreased. In addition, the humoral immune response to a T cell–dependent antigen is impaired. VCAM-1 serves an important role for B cell localization and the T cell–dependent humoral immune response.

The ontogeny and function of gut-associated-lymphoid tissue is known to be critically dependent on the β7 integrin subfamily. We have investigated the development of intestinal inflammation and pathogen-specific protective immunity to enteric helminth infection in β7 integrin knockout (KO) mice. During Trichinella spiralis infection of the small intestine there was a significant delay and reduction in the magnitude of intestinal eosinophilia and mastocytosis in the absence of β7 integrin, resulting in impaired host protection. Aberrant distribution of mast cells was also observed in the small intestine of infected KO mice. Adoptive transfer of primed wild-type mesenteric lymph node cells into T. spiralis-infected β7 KO mice did not restore the intestinal mast cell response, suggesting that the defect in intestinal mastocytosis is due to the absence of β7 expression on this population rather than an indirect consequence of reduced T cell numbers. In contrast, no impairment in leukocyte recruitment or protection against Trichuris muris infection of the large intestine was observed in KO mice. Taken together the data provide the first description of reduced leukocyte homing and attenuated protective immunity against helminth infection in β7 KO mice. Furthermore, these results suggest that β7 integrin-independent adhesion molecule interactions are deployed in the large but not small intestine during intestinal inflammation.

In this work, a theoretically predicted electrolyte composition comprising 6 M potassium hydroxide (KOH), 2 M citric acid, 1 M glycine, and 0.5 M zinc oxide is tested in terms of electrochemical performance, cathode stability, and electrolyte stability. It is shown that dissolved metal ions from the cathode reacted with the introduced organic additives, reduced the cathode stability, and blocked metal oxidation reactions. This was due to a Kolbe-like decomposition reaction that occurred because of the presence of potassium citrate, which formed because of the reaction of KOH and citric acid. Furthermore, intermediate products of this decomposition reaction appeared to block the cathode's surface, hindering oxygen (O2) evolution and reducing the overall cell performance. The decomposition of potassium citrate starts above 1.7 V Zn. Additionally, it is shown that tribase citric acid behaves similarly to a dibase carbonic acid. Both decrease the onset potential for the O2reduction reaction from 0.9 V vs reversible hydrogen electrode (RHE) for pure 6 M KOH to 0.6 V vs RHE for KOH with these organic acids.

Mesenteric lymph nodes (MLN) drain the gut where nutritive antigens and pathogens are encountered by lymphocytes of the gut-associated lymphoid tissue. We sought to determine how lymphocytes enter the MLN by studying mice double deficient for β7 integrins and L-selectin. β7/L-selectin double-deficient lymphocytes did not migrate into MLN. Most importantly, MLN formation was drastically impaired in β7/L-selectin double-deficient mice. Lymphocyte numbers in MLN from β7/L-selectin double-deficient mice were tenfold reduced compared to control mice. A high percentage of the few lymphocytes still detected in MLN from β7/L-selectin double-deficient mice were CD44^hi CD18^hi , suggesting alternate migration pathways independent of L-selectin and β7 integrin for these cells. We conclude that the combination of both molecules, L-selectin and β7 integrin, is indispensable for MLN formation and that these molecules may mediate lymphocyte migration to MLN in a sequential and synergistical manner.

The requirement of β7 integrins for lymphocyte migration was examined during an ongoing immune response in vivo. Transgenic mice (OT-I) expressing an ovalbumin-specific major histocompatibility complex class I–restricted T cell receptor for antigen were rendered deficient in expression of all β7 integrins or only the αEβ7 integrin. To quantitate the relative use of β7 integrins in migration in vivo, equal numbers of OT-I and OT-I-β7−/− or OT-I-αE−/− lymph node (LN) cells were adoptively transferred to normal mice. Although OT-I-β7−/− LN cells migrated to mesenteric LN and peripheral LN as well as wild-type cells, β7 integrins were required for naive CD8 T cell and B cell migration to Peyer's patch. After infection with a recombinant virus (vesicular stomatitis virus) encoding ovalbumin, β7 integrins became critical for migration of activated CD8 T cells to the mesenteric LN and Peyer's patch. Naive CD8 T cells did not enter the lamina propria or the intestinal epithelium, and the majority of migration of activated CD8 T cells to the small and large intestinal mucosa, including the epithelium, was β7 integrin–mediated. The αEβ7 integrin appeared to play no role in migration during a primary CD8 T cell immune response in vivo. Furthermore, despite dramatic upregulation of αEβ7 by CD8 T cells after entry into the epithelium, long-term retention of intestinal intraepithelial lymphocytes was also αEβ7 independent.

The paper focuses on the performance and aging behavior of lithium nickel cobalt manganese oxide commercial standard material (NCM-111) which is improved with a post synthesis process in order to enhance the cathode active material of lithium-ion pouch cells regarding their capacity and cyclic stability. The aging behavior of the cells is analyzed with electrochemical impedance spectroscopy (EIS) during long-term electrochemical load cycling tests based on the Common Artemis Driving Cycle (CADC). Additionally, post-mortem investigations using scanning electron microscopy (SEM) and X-ray diffraction (XRD) were performed. The results demonstrate that post-processing of electrode active material is an effective tool to improve the properties of lithium-ion electrode materials, especially regarding high energy applications and lifetime optimization. The paper bridges the gap between lithium-ion battery electrode material development and the necessary cell testing under automotive relevant conditions which is important for the evaluation of new lithium-ion battery materials for automotive applications.

Because integrins 47 and E7 contribute to epidermotropism of T-cells during skin inflammation, we sought to study their role in skin allograft rejection.

We develop a thermally sprayed Ti coating for PEMFC stainless steel (ss) bipolar plates. It is subsequently modified with Au by electro-deposition. SEM reveals that the Au/Ti coating is 30.8 µm thick and rough. The presence of TiO2between Ti and Au is negligible, as confirmed by XRD and XPS. Potendiodynamic characteristics in O2-saturated 0.5 M H2SO4show that the Au/Ti/ss samples have comparable corrosion currents to Au/ss but higher corrosion potentials. The interfacial contact resistance (ICR) of Au/Ti/ss is 8.6 mΩ cm2 under a compaction pressure of 140 N cm-2. The performances of PEMFCs with Au and Au/Ti are similar at cell voltages higher than 0.75 V. However, at 0.6 V the Au/Ti coating diminishes the current and pressure instabilities of the PEMFC operating under strong flooding conditions. The effect also occurs in the oscillation frequency, confirming the unique property of Au/Ti for reducing the effect of flooding.

PEM electrolysis is a promising technology for large scale storage of surplus electricity, though it is still costly mainly due to the manufacture of large area and high purity Ti bipolar plates (BPP). In this work we have developed an Au/Ti coating deposited by electrodeposition/thermal spraying on stainless steel BPP. The coating was physically characterized with SEM and electro-chemically evaluated in simulated anode conditions. Interfacial contact resistance (ICR) vs. compaction pressure measurements showed that the coating is highly conductive. It successfully protected the stainless steel substrate from corrosion. However, the Au modification detached after 6 h of application of a potential of 2 V vs. RHE. Consequently the Au modification has to be replaced by either another precious metal or a corrosion resistant electro-ceramic. The coating reported herein could have a large impact on the cost of PEM electrolyzers for large scale electricity storage from renewables.

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