76,790 research outputs found
Data for: Modeling urban growth by coupling localized spatio-temporal association analysis and binary logistic regression
No full textThis dataset includes three excel sheets containing the original neighborhood aggregation index (NAI) calculated for sampled points for urbanized land cover type, at different neighborhood sizes (3×3, 5×5, 7×7, 9×9, and 11×11) and time windows (T1: 2016, T2: 2015-2016, and T3: 2014-2016)
Significantly Enhanced Oxygen Transport Properties in Mixed Conducting Perovskite Oxides under Humid Reducing Environments
No full textMixed ionic and electronic conducting (MIEC) perovskite oxides (ABO(3)) have a substantial role in carbon-neutral clean energy conversion and storage technologies. Owing to their favorable catalytic properties, high ionic and electronic conductivity, and chemical and redox stability, MIEC perovskite oxides are promising electrode materials in multiple applications, such as solid oxide fuel/electrolysis cells, oxygen transport membranes, metal-air batteries, electrochemical sensors, and electrocatalysts for water splitting. Here, taking (La0.8Sr0.2)(0.95)Cr0.5Fe0.5O3-delta (LSCrF8255) as a model MIEC perovskite oxide, we demonstrate that the oxygen mass transport properties are significantly enhanced under a humid reducing water vapor environment (pO(2) < 1 mbar, pH(2)O = 30 mbar) by up to 4 orders of magnitude compared to those measured under dry (pO(2) = 200 mbar) and wet (pO(2) = 200 mbar, pH(2)O = 30 mbar) oxygen atmospheres. A 0.8 eV decrease in the activation energy for oxygen bulk diffusion was also found under water vapor, and a decrease in activation energy of 0.7 eV for water surface exchange compared to oxygen surface exchange was found. The mechanisms underpinning these enhancements were explored. Furthermore, LSCrF8255 has also exhibited a consistent surface composition evolution regarding Sr segregation and phase separation and an excellent bulk stability under both oxidizing and reducing environments at elevated temperatures
21. Zenkoku Suihei-sha
No full textIwao Seiichi, Iyanaga Teizō, Ishii Susumu, Yoshida Shōichirō, Fujimura Jun'ichirō, Fujimura Michio, Yoshikawa Itsuji, Akiyama Terukazu, Iyanaga Shōkichi, Matsubara Hideichi. 21. Zenkoku Suihei-sha. In: Dictionnaire historique du Japon, volume 20, 1995. Lettres U, V, W, X, Y et Z. pp. 135-136
21. Zenkoku Suihei-sha
No full textIwao Seiichi, Iyanaga Teizō, Ishii Susumu, Yoshida Shōichirō, Fujimura Jun'ichirō, Fujimura Michio, Yoshikawa Itsuji, Akiyama Terukazu, Iyanaga Shōkichi, Matsubara Hideichi. 21. Zenkoku Suihei-sha. In: Dictionnaire historique du Japon, volume 20, 1995. Lettres U, V, W, X, Y et Z. pp. 135-136
The Benefits of Being Economics Professor A (and not Z)
No full textAlphabetic name ordering on multi-authored academic papers, which is the convention in the economics discipline and various other disciplines, is to the advantage of people whose last name initials are placed early in the alphabet. As it turns out, Professor A, who has been a first author more often than Professor Z, will have published more articles and experienced afaster growth rate over the course of her career as a result of reputation and visibility. Moreover, authors know that name ordering matters and indeed take ordering seriously: Several characteristics of an author group composition determine the decision to deviate from the default alphabetic name order to a significant extent.performance measurement, incentives, economists, name ordering
Final word on Jersey Dutch
No full textIn this article, William Z. Shetter compares and contrasts the dialects that developed between different Dutch colonies in the New World. He explores in-depth the nuances of Jersey Dutch, and provides theories to explain how Dutch and colonial languages blended. The article is reprinted from American Speech, December 1958, Volum XXXIII, No. 4
Understanding surface chemical processes in perovskite oxide electrodes
No full textThe effect of operating conditions on the surface composition and evolution of (La0.8Sr0.2)0.95Cr0.5Fe0.5O3−δ (LSCrF8255) as a model perovskite oxide was investigated. LSCrF8255 pellets were annealed under dry oxygen (pO2 = 200 mbar), wet oxygen (pO2 = 200 mbar, pH2O = 30 mbar), and water vapour (pO2 < 1 mbar, pH2O = 30 mbar) environments to reflect the applications of perovskite materials as electrodes for oxygen reduction/evolution and H2O electrolysis in electrochemical energy conversion devices such as solid oxide fuel/electrolysis cells (SOFCs/SOECs) and oxygen transport membranes (OTMs). A series of comprehensive surface characterization techniques were applied, including low energy ion scattering spectroscopy (LEIS), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), and energy-dispersive X-ray spectroscopy (EDX). Our comprehensive study showed that after annealing at 900 °C for 27 hours, a severe level of Sr surface segregation occurred on the sample annealed in both dry oxygen and water vapour but in different manners, whereas on the sample annealed in wet oxygen, Sr segregation was likely suppressed. In addition, the Sr segregation behaviour can be correlated to other mass transport phenomena, such as Cr evaporation and redeposition and Si deposition, as well as to crystal orientation and defects such as grain boundaries and dislocations. Apart from the Sr-enriched surface precipitates, phase separation was consistently observed on the samples annealed in all three conditions. The secondary phase was found to be B-site cation enriched (significantly Fe enriched, relatively Cr enriched) and A-site cation (La and Sr) deficient. Moreover, in contrast to the Sr enriched surface, a La enriched surface was observed on samples annealed in dry oxygen at 600 and 700 °C, which was found to be potentially caused by the Sr and Cr surface evaporation processes
SHA DEP-EI-mass spectrum compared with predicted peaks.
No full textIn blue are all plotted peaks observed in the spectrum for the SHA peptide. In green are peaks that match with predictions generated using our model. Red squares mark peaks associated with protecting groups used in the synthesis of the peptides. A peak was considered a match if it was within the max instrumental error (+/- 0.25 m/z) of the mass spectrometer. (TIF)</p
Oxygen diffusion behaviour of A-site deficient (La0.8Sr0.2)0.95Cr0.5Fe0.5O3-δ perovskites in humid conditions
No full textIn the development of high temperature electrochemical devices such as oxygen transport membranes (OTMs) and solid oxide fuel cells (SOFCs), solid-state (ceramic) technologies have proven to be particularly promising. For example, doped lanthanum chromite perovskites, which display high thermo-chemical stability in aggressive environments as mixed ionic and electronic conducting (MIEC) perovskite electrodes, show potential for use as OTMs. Previous studies on the range of these MIEC perovskites have focussed on material behaviour under pure oxygen conditions. Recently, however, it has been suggested that components of air such as humid vapour may modify the materials' chemistry under device operating conditions, affecting device performance and durability. We have designed and carried out fundamental research into the effect of humidity on the oxygen surface exchange and diffusion kinetics of a commercialized (La0.8Sr0.2)0.95Cr0.5Fe0.5O3−δ (LSCrF8255) perovskite material under elevated OTM and SOFC operating conditions. The water surface exchange and oxygen ion diffusion behaviour of LSCrF8255 perovskites were measured through Isotopic Exchange Depth Profiling-Secondary Ion Mass Spectrometry (IEDP-SIMS) in a designed humid condition with an oxygen partial pressure of 200 mbar and a constant water vapour pressure of 30 mbar, from intermediate to high temperatures (600 °C to 900 °C). Our study demonstrates consistency between oxygen ion bulk diffusion kinetics in wet (pO2 = 200 mbar, pH2O = 30 mbar) and dry (pO2 = 200 mbar, pH2O = 0 mbar) oxygen atmospheres. However, limited surface exchange between water and the LSCrF material was observed above 800 °C. To study the limited water surface exchange behaviour, angle-resolved X-ray photoelectron spectroscopy (ARXPS), scanning electron microscopy (SEM), and scanning transmission electron microscopy (STEM) have been applied to correlate the changes in water surface exchange with chemical or topographic changes in the materials, such as Sr surface segregation processes. It was found that Sr segregation is one of the factors suppressing water surface exchange, although not the primary limiting factor. Another limiting factor was found through in situ residual gas analysis (RGA), which showed the dominance of homo-exchange between the humid vapour and gaseous oxygen molecules at high temperatures
Improving security of lightweith SHA-3 against preimage attacks
No full textIn this article we describe the SHA-3 algorithm and its internal permutation in which potential weaknesses are hidden. The hash algorithm can be used for different purposes, such as pseudo-random bit sequences generator, key wrapping or one pass authentication, especially in weak devices (WSN, IoT, etc.). Analysis of the function showed that successful preimage attacks are possible for low round hashes, protection from which only works with increasing the number of rounds inside the function. When the hash function is used for building lightweight applications, it is necessary to apply a small number of rounds, which requires additional security measures. This article proposes a variant improved hash function protecting against preimage attacks, which occur on SHA-3. We suggest using an additional external randomness sources obtained from a lightweight PRNG or from application of the source data permutation
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