a b s t r a c tSome compositions of ceramic hydrogen permeable membranes are promising for integration in high temperature processes such as steam methane reforming due to their high chemical stability in large chemical gradients and CO 2 containing atmospheres. In the present work, we investigate the hydrogen permeability of densely sintered ceramic composites (cercer) of two mixed ionic-electronic conductors: La 27 W 3.5 Mo 1.5 O 55.5 À δ (LWM) containing 30, 40 and 50 wt% La 0.87 Sr 0.13 CrO 3 À δ (LSC). Hydrogen permeation was characterized as a function of temperature, feed side hydrogen partial pressure (0.1-0.9 bar) with wet and dry sweep gas. In order to assess potentially limiting surface kinetics, measurements were also carried out after applying a catalytic Pt-coating to the feed and sweep side surfaces. The apparent hydrogen permeability, with contribution from both H 2 permeation and water splitting on the sweep side, was highest for LWM70-LSC30 with both wet and dry sweep gas. The Pt-coating further enhances the apparent H 2 permeability, particularly at lower temperatures. The apparent H 2 permeability at 700 1C in wet 50% H 2 was 1.1 Â 10 À 3 mL min À 1 cm À 1 with wet sweep gas, which is higher than for the pure LWM material. The present work demonstrates that designing dual-phase ceramic composites of mixed ionic-electronic conductors is a promising strategy for enhancing the ambipolar conductivity and gas permeability of dense ceramic membranes.

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First review of supported molten-salt membranes highlighting materials challenges, mechanistic development and manufacturing opportunities towards energy applications.

Oxygen permeation measurements are performed on dense samples of CaTi0.85Fe0.15O3-δ, CaTi0.75Fe0.15Mg0.05O3-δ and CaTi0.75Fe0.15Mn0.10O3-δ in combination with density functional theory (DFT) calculations and X-ray photoelectron spectroscopy (XPS) in order to assess Mg and Mn as dopants for improving the O2 permeability of CaTi1-xFexO3-δ based oxygen separation membranes. The oxygen permeation measurements were carried out at temperatures ranging between 700-1000 °C with feed side oxygen partial pressures between 0.01-1 bar. The O2 permeability was experimentally found to be highest for the Mn doped sample over the whole temperature range, reaching 4.2×10 -3 ml min -1 cm -1 at 900 °C and 0.21 bar O2 in the feed which corresponds to a 40% increase over the Fe-doped sample and similar to reported values for x=0.2. While the O2 permeability of the Mg doped sample was also higher than the Fe-doped sample, it approached that of the Fe-doped sample above 900 °C. According to the DFT calculations, Mn introduces electronic states within the band gap and will predominately exist in the effectively negative charge state, as indicated by XPS measurements. Mn may therefore improve the ionic and electronic conductivity of CTF based membranes. The results are discussed in terms of the limiting species for ambipolar transport and O2 permeability, i.e., oxygen vacancies and electronic charge carriers.

In this multicenter study of 328 twin pregnancies with Type-III selective intrauterine growth restriction (sIUGR), fetal death complicated 11% of them. At viability, mortality rates were very low (< 2% at 28 weeks). Delivery at 32 weeks was associated with a high rate of adverse neonatal outcome, which substantially decreased at 34 weeks (11%), with a very low risk of fetal death (0.7%). What are the clinical implications of this work? With close fetal surveillance, the risk of unexpected fetal death in Type-III sIUGR may be lower than reported previously. Further multicenter studies are needed to assess which factors truly predict fetal death, in order to allow for optimal pregnancy management.

The electrical conductivity of TiNb2O7 was characterized as a function of temperature, pO2 and pH2O. The total conductivity was independent of pO2 in the low oxygen partial pressure regime, while a dependency of pO2 −1/4 was observed at higher oxygen partial pressures. The conductivity increased with increasing pH2O under oxidizing conditions below 700°C. Mixed electronic and protonic conduction was indicated by H/D isotope exchange and transport number measurements. A defect model based on interstitial type of hydration was established and fitted to the conductivity data allowing for determination of physicochemical parameters of hydration and electron migration.

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