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The conductivity of Gd2Ti2O7 with irradiation-induced structural disorder increased with disorder as the material transformed from ordered pyrochlore to defect-fluorite.

Efficient conversion of methane to value-added products such as olefins and aromatics has been in pursuit for the past few decades. The demand has increased further due to the recent discoveries of shale gas reserves. Oxidative and non-oxidative coupling of methane (OCM and NOCM) have been actively researched, although catalysts with commercially viable conversion rates are not yet available. Recently, Sr 2 F e 1.5 + 0.075 M o 0.5 O 6 − δ (SFMO-075Fe) has been reported to activate methane in an electrochemical OCM (EC-OCM) set up with a C2 selectivity of 82.2%1. However, alkaline earth metal-based materials are known to suffer chemical instability in carbon-rich environments. Hence, here we evaluated the chemical stability of SFMO in carbon-rich conditions with varying oxygen concentrations at temperatures relevant for EC-OCM. SFMO-075Fe showed good methane activation properties especially at low overpotentials but suffered poor chemical stability as observed via thermogravimetric, powder XRD, and XPS measurements where SrCO3 was observed to be a major decomposition product along with SrMoO3 and MoC. Nevertheless, our study demonstrates that electrochemical methods could be used to selectively activate methane towards partial oxidation products such as ethylene at low overpotentials while higher applied biases result in the complete oxidation of methane to carbon dioxide and water. Catalytic conversion of methane to ethene is limited by poor conversion, selectivity, and catalyst stability. Here a solid oxide electrolysis process is reported as a promising method for selective, partial oxidation of methane with low overpotentials. [ABSTRACT FROM AUTHOR]

Molybdenum carbide has immense potential as an active catalyst for reaction systems such as synthesis of important chemicals like ammonia. However, the carbide is not used as a commercial catalyst or support as the current synthesis processes produce low surface area material or have contaminants such as excess carbon and surface and chemisorbed oxygen. Moreover, attempts to refine the synthesis pathways are usually not supported by any thermochemical modeling. In this study, a facile and reproducible method to synthesize high surface area molybdenum carbide was developed with the help of thermochemical modeling to better understand molybdenum‐carbon phase behavior. We have synthesized 2‐5 nm particles of MoxC with surface areas of up to 360 m2/g as characterized using a variety of techniques including X‐ray diffraction and electron microscopy. Refining synthesis pathways using thermochemical modeling. [ABSTRACT FROM AUTHOR]

The continuous monitoring of the conversion, of Y, Cu and BaF precursors to form superconductor thin films has been achieved using a fluorine-specific-ion electrode immersed in an effluent gas-washing cell. High-quality thin films of YBaCuO deposited on NdGaO, LaA10 and LaGaO, have been produced by limiting the wet oxygen annealing phase of the post-deposition anneal. When the films were over-annealed in humidified oxygen the superconducting transition temperature as measured by inductive methods and the crystal quality, determined by x-ray rocking curves were degraded. [ABSTRACT FROM AUTHOR]

The article focuses on advancement and development of various technologies which will be effective against fighting drastic weather natural disaster. It highlights the importance of renewable energy technology and mentions the role of battery-powered portable communications and sensors on saving lives during natural disaster. It informs that fuel cells are able to supply uninterrupted power to society which can be used as major advances for fighting disaster.