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Self-generated composites from the series BaCe1-(x+z)FexYzO3-ẟ with z=0.2 for 0.1≤x≤0.6 and z=0 for Ce:Fe = 1 were obtained by one-pot synthesis. The composites consist of proton and electron conducting phases and are interesting as electrode materials for protonic ceramic fuel and electrolyser cells. X-ray diffraction with quantitative phase analysis and scanning electron microscopy with energy-dispersive X-ray spectroscopy showed that the materials consist of Fe-rich phases and a Ce-rich perovskite phase, which are present in the corresponding proportion depending on the precursor composition (Ce-Fe ratio). Substitution with Y leads to a narrowing of the miscibility gap compared to BaCe1-xFexO3-ẟ composites, thus favouring transformation of the composites into single cubic phases at temperatures above 1000°C. Further, Y influences the mutual solubility of Fe3+/4+ and Ce4+ in the Ce-rich and Fe-rich phase, respectively, as shown elemental mapping via scanning transmission electron microscopy. As only a small proportion of the Y dissolves in the electrolyte-type phase, the increased proton uptake resulting from the incorporation of Y in the Ce-rich phase is limited. Strategies to overcome this limitation by substitution with ions with similar ionic radii, but different basicity, are discussed.

Die autosomal-dominanten Genodermatosen Morbus Darier und Morbus Hailey-Hailey stellen Dermatologen vor besondere Herausforderungen. Trotz ahnlicher Pathogenese, die in einer verminderten Adhasion suprabasaler Keratinozyten aufgrund defekter ATPasen in epidermalen Calciumkanalen besteht, unterscheiden sich die beiden Erkrankungen in klinischem Bild und Therapiemoglichkeiten erheblich. Der Morbus Darier ist gekennzeichnet durch braunlich-erythematose, keratotische Papeln in seborrhoischen und intertriginosen Arealen, welche zu grosflachigen Lasionen konfluieren konnen. Betroffene mit Morbus Hailey-Hailey entwickeln vornehmlich intertriginos Papulovesikel und Blaschen, aus denen oft erythematose Plaques mit Erosionen und schmerzhaften Fissuren entstehen. Die Lebensqualitat ist aufgrund von Beschwerden (Juckreiz, Brennen, Schmerzen), Korpergeruch und des chronischen Verlaufs deutlich eingeschrankt. Die Therapieoptionen sind immer noch limitiert. Antiseptika und topische Glukokortikoide bilden eine wichtige Saule der Therapie, bei Superinfektionen ist oft eine systemische antiinfektiose Therapie erforderlich. Ablative Masnahmen wie Dermabrasion und CO2 -Laser-Therapie konnen bei intertriginosem Morbus Hailey-Hailey zu langfristiger Erscheinungsfreiheit fuhren, temporare Besserungen wurden auch durch intralasionale Botulinumtoxin-Injektionen erzielt. Unter den Systemtherapeutika liegt beim Morbus Darier die beste Evidenz fur das hierfur zugelassene Acitretin vor. Die Wirksamkeit von Immunsuppressiva und -modulatoren ist uneinheitlich. Niedrig dosiertes Naltrexon zeigt bei Morbus Hailey-Hailey zufriedenstellendere Ergebnisse als bei Morbus Darier. Der vorliegende CME-Artikel fasst das aktuelle Wissen uber die beiden Dermatosen unter Berucksichtigung neuer Entwicklungen zusammen.

Compounds from the series La0.8-xNdxCa0.2FeO3-δ (0.1 ≤ x ≤ 0.7) were synthesised by a sol–gel route. X-ray diffraction and Rietveld analysis showed that materials with 0 ≤ x ≤ 0.6 crystallize as single-phase orthorhombic perovskites. The smaller ionic radius of Nd3+ compared to La3+ leads to a decrease in unit cell volume with increasing x. Elemental mapping by high-resolution scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy confirms the homogeneous distribution of the A-site elements (La, Nd and Ca) in the perovskite (ABO3) lattice. The thermal expansion behaviour of La0.8-xNdxCa0.2FeO3-δ (0 ≤ x ≤ 0.6) was characterized by dilatometry at 30 ≤ T/°C ≤ 1000 and 1 × 10–3 ≤ pO2/bar ≤ 1. The thermal expansion coefficients of La0.8-xNdxCa0.2FeO3-δ, which were determined in regions I (40–530 °C) and II (530–990 °C), respectively, are almost independent of the Nd concentration in the range of (0 ≤ x ≤ 0.6) and increase slightly with decreasing pO2. The transition from orthorhombic to trigonal modification, which is observed for La0.8Ca0.2FeO3-δ at approx. 740 °C, is suppressed for all Nd-substituted compounds with x ≥ 0.1.

Since the development of MEMS heating holders, dynamic in-situ experiments at elevated temperatures may be complemented by X-ray spectrometry for chemical analysis. Although the amount of IR radiation is small when compared to furnace holders, the influence of IR radiation emitted from the heating device on the quality of the X-ray spectra is significant. In this work, we systematically examine the influence of infrared (IR) radiation generated by MEMS-based in situ heating systems (DENSsolutions single- and double-tilt holders) on the results and interpretation of energy-dispersive X-ray (EDX) spectra through simulation and measurement. Focal points of interest in this study are the influence of holder geometry, shadowing and orientation with respect to the different emission characteristics of IR and X-ray photons and their interaction with a side-entry and a multi-detector system. IR photons substantially contribute to count rates, dead time, electronic noise levels, energy resolution, and detection efficiency of semiconductor detectors. At higher sample temperatures, they ultimately limit the feasibility of EDXS for elemental characterization and especially the traceability of low-Z elements. This work provides a quantitative insight into the influence of all relevant parameters related to in situ heating experiments on the spectral quality. Bearing this in mind, we aim to provide a guide to optimizing in situ heating experiments with respect to chemical EDXS analysis.

Linear IgA bullous dermatosis (LABD) is a rare subepidermal autoimmune blistering disease characterized by linear deposition of IgA along the basement membrane zone. Although most reported cases are idiopathic, there is a subset of patients with drug-induced LABD. Various drugs have been associated with the drug-induced form of the disease. This paper reviews the literature on drugs reported to elicit linear IgA dermatosis and its specific clinical presentation. In addition, a case report of a 77-year-old male patient with linear IgA dermatosis induced by vancomycin is described. The aim of this paper is to emphasize the need to include this differential diagnosis in cases of suspected adverse drug reactions, as well as to highlight the role of drugs in LABD.

The autosomal-dominant genodermatoses Darier disease and Hailey-Hailey disease present special challenges to dermatologists. Despite their similar pathogenesis featuring impaired adhesion of suprabasal keratinocytes as a result of defective ATPases in epidermal calcium channels, the two diseases differ considerably in clinical presentation and therapeutic options. Darier disease is characterized by reddish brown, keratotic papules in seborrheic and intertriginous areas, which may coalesce into extensive lesions. Individuals affected with Hailey-Hailey disease primarily develop intertriginous papulovesicles and small blisters, which often evolve into erythematous plaques with erosions and painful fissures. Quality of life is significantly reduced because of complaints (itch, burning sensation, pain), body malodor and chronicity. Therapeutic options remain limited. Antiseptics and intermittent topical corticosteroids are a cornerstone of therapy, and systemic anti-infective treatment is often required in cases of superinfection. Ablative surgical interventions such as dermabrasion and CO2 laser surgery can lead to long-term remissions in intertriginous Hailey-Hailey disease, while temporary relief may also be achieved by intralesional injections of botulinum toxin. Of the systemic medications available for Darier disease, acitretin, which is approved for this purpose, has the best supporting evidence. The efficacy of immunosuppressants and immune modulators is inconsistent. Low-dose naltrexone produces more satisfactory results in Hailey-Hailey than Darier disease. The present CME article summarizes current knowledge of the two dermatoses, taking recent developments into account.

High-resolution STEM-EELS provides information about the composition of crystalline materials at the atomic scale, though a reliable quantitative chemical analysis is often hampered by zone axis conditions, where neighbouring atomic column intensities contribute to the signal at the probe position. In this work, we present a procedure to determine the concentration of two elements within equivalent atomic columns from EELS elemental maps – in our case barium and lanthanum within the A-sites of Ba1.1La1.9Fe2O7, a second order Ruddlesden-Popper phase. We took advantage of the large changes in the elemental distribution from column to column and introduced a technique, which substitutes inelastic scattering cross sections during the quantification step by using parameters obtained from the actual experiment. We considered channelling / de-channelling effects via inelastic multislice simulations and were thereby able to count occupancies in each atomic column. The EELS quantification results were then used as prior information during the Rietveld refinement in XRD measurements in order to differentiate between barium and lanthanum.

Correction for ‘Influence of Y-substitution on phase composition and proton uptake of self-generated Ba(Ce,Fe)O3−δ–Ba(Fe,Ce)O3−δ composites’ by Christian Berger et al., J. Mater. Chem. A, 2022, 10, 2474–2482, https://doi.org/10.1039/D1TA07208K.

Micro- and nanostructure investigations of AlSi10Mg alloy powders and additive manufactured samples were performed to highlight common effects related to very fast local cooling rates during production. We refer to the homogenously dispersed Si(Mg) nanoparticles and the presence of interconnected amorphous phases in the coral-like eutectic Si network and their evolution upon in-situ heating in scanning transmission electron microscope. The in-situ heating experiments showed as first phenomenon at lower temperatures the crystallization of the eventually present amorphous silicon, while at temperatures above 240 °C coarsening into spherical crystalline particles and network breakage prevail. In addition, the Si nanoparticles evolved, mainly changing their shape and coherence with the matrix. These findings correlate with results from macroscopic investigations (DSC, in-situ XRD), where they further contribute to explain the retrieved exothermic signals by linking them to the respective crystallization of the amorphous Si network, the coarsening of the finely dispersed Si nanocrystals and network breakage.

Long-term stability tests are performed at 800 °C on Pr2NiO4+δ air electrodes by use of a symmetrical button cell with Ce0.9Gd0.1O1.95 as solid electrolyte. The experiments are carried out by means of electrochemical impedance spectroscopy and current-voltage measurements with and without current load under dry and humid conditions in the presence of a chromium source. Chromium poisoning of Pr2NiO4+δ air electrodes is investigated for periods of several hundred hours at 30% relative humidity. In order to separate the influence of anodic and cathodic electrode polarization on Cr-deposition, measurements are conducted using a Pt-reference electrode. The electrode performance is found to remain fairly stable under dry conditions, even when a current is drawn. However, after volatile Cr-species in a humid atmosphere are introduced, the cell performance starts to deteriorate and the polarization resistance contribution of the SOFC cathode increases significantly. After several thousand hours, the electrodes are analyzed by means of analytical electron microscopy. Detailed post-test analyses provide evidence for a correlation between the extent of Cr-deposition and electrode degradation in SOFC as well as SOEC mode. Based on these findings, enhanced resilience of Pr2NiO4+δ against Cr-poisoning in SOEC mode can be established.