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We present a study of the fabrication of thin films from a Li 7 La 3 Zr 2 O 12 (LLZO) target using pulsed laser deposition. The effects of substrate temperatures and impurities on electrochemical properties of the films were investigated. The thin films of Li-La-Zr-O were deposited at room temperature and higher temperatures on a variety of substrates.Deposition above 600 °C resulted in a mixture of cubic and tetragonal phases of LLZO, as well as a La 2 Zr 2 O 7 impurity, and resulted in aluminum enrichment at the surface when Al-containing substrates were used. Films deposited at 600 °C exhibited the highest room temperature conductivity, 1.61×10 -6 S/cm. The chemical stability toward metallic lithium was also studied using X-ray photoelectron spectroscopy, which showed that the oxidation state of zirconium remained at +4 following physical contact with heated lithium metal.

IL-33 may down-regulate CLDN1 expression through the ERK/STAT3 pathway in keratinocytes.

High-temperature chemical reactions are ubiquitous in (electro) chemical applications designed to meet the growing demands of environmental and energy protection. However, the fundamental understanding and optimization of such reactions are great challenges because they are hampered by the spontaneous, dynamic, and high-temperature conditions. Here, we investigated the roles of metal catalysts (Pd, Ni, Cu, and Ag) in the high-temperature reverse water-gas shift (RWGS) reaction using in-situ surface analyses and density functional theory (DFT) calculations. Catalysts were prepared by the deposition-precipitation method with urea hydrolysis and freeze-drying. Most metals show a maximum catalytic activity during the RWGS reaction (reaching the thermodynamic conversion limit) with formate groups as an intermediate adsorbed species, while Ag metal has limited activity with the carbonate species on its surface. According to DFT calculations, such carbonate groups result from the suppressed dissociation and adsorption of hydrogen on the Ag surface, which is in good agreement with the experimental RWGS results.

SummaryObjective To evaluate type I hypersensitivity to citrus red mite (Panonychus citri), its prevalence, and relationship to respiratory dysfunction, a cross-sectional survey was performed among citrus farmers on Cheju Island, Korea. Materials and methods Questionnaires, and skin prick test responses to 11 common inhalant allergens and citrus red mite were performed in 181 citrus farmers, and serumspecific IgE antibodies to citrus red mite were measured by ELISA in sera of 123 subjects. To determine airway hyperresponsiveness, methacholine bronchial provocation tests were performed in 55 subjects who complained of recurrent lower respiratory symptoms. Results The prevalence of asthma-based on presence of asthmatic symptoms on the questionnaire and airway hyperresponsiveness to methacholine, and allergic rhinitis based on presence of nasal symptoms on the questionnaire and positive skin-test response were 12.1% and 19.3%, respectively. The positive rate of skin responses to one or more of 11 common inhalant allergens excluding citrus red mite was 17.1%, and if citrus red mite was included, 25.9% of farmers had positive responses. On skin prick tests, citrus red mite (16.5%) was the most common sensitizing allergen, followed by cockroach (11.0%), Dermatophagoides pteronyssinus (9.9%), and D. farinae (9.3%). Among farmers with asthma and allergic rhinitis, the positive skin responses to citrus red mite were noted in 54.5 and 68.5%, respectively. Serum-specific IgE antibodies to citrus red mite were detected in 45 farmers (36.5%) of the 123 tested, and there was significant correlation between specific IgE level and weal (A/H ratio) to citrus red mite (r ¼ 0.57, P < 0.001). The prevalence of asthma was higher in subjects with positive skin responses or high serum-specific IgE antibodies to citrus red mite than in those without skin response or serum specific IgE (P < 0.05, respectively). Conclusion Citrus red mite is the most important allergen in citrus farmers with asthma and rhinitis in which causative allergen has not been identified. It should be included in the skin test battery for screening the causative allergen in farmers exposed to citrus red mite.

The performance of solid oxide fuel cells (SOFCs) with thin film electrolytes and electrodes was investigated at a lower operating temperature regime (T≤600°C) . 2×2cm anode-supported unit cells with thin film components of a Ni–yttria-stabilized zirconia (YSZ) composite anode interlayer, a thin (≤1μm) YSZ electrolyte, and a lanthanum strontium cobalt oxide cathode were fabricated by using pulsed laser deposition, and the performance of the cells was characterized at the temperature range of 350°C≤T≤600°C . Stable open-circuit voltage values above 1 V were successfully obtained with thin film electrolyte cells, which implied that the 1μm thick electrolyte was fairly dense and gastight. The thin film electrolyte cells exhibited a much more improved cell performance than a thick film (∼8μm) YSZ electrolyte cell at the low operating temperature regime (350–550°C) and, in some cases, showed better power outputs than other thin film membrane micro-SOFCs.

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Atomic layer deposition (ALD) is a powerful tool for nanoscale film deposition. It can uniformly deposit films at a monolayer level even in complex 3D structures, while the deposition temperature is relatively low with its potential scalability. In this work, surface tuning of solid oxide fuel cell (SOFC) cathodes is successfully demonstrated by modifying the surface of La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) with nanoscale lanthanum strontium cobaltite (LSC) using ALD. The ALD‐LSC surface‐tuning layer can enhance the charge transfer kinetics at the cathode surface, while the backbone LSCF cathode provides a means for ionic and electronic transport. Microstructural analysis shows that the ALD‐LSC on LSCF has excellent step coverage, which is enabled by the conformal characteristic of the ALD process. It is found that the electrochemical performance of SOFCs can be enhanced enormously by surface tuning of the cathodes with nanoscale LSC film corresponding to 1–12 nm. Using density functional theory calculations, the enhanced catalytic activity of the surface‐tuned SOFC cathode using ALD‐LSC could be confirmed. This result demonstrates the possibility of nanoscale surface tuning of SOFC cathodes by using the ALD process to improve the surface activity.