Ammonia (NH) production in 2023 reached 150 million tons and is associated with potential concomitant production of up to 500 million tons of CO each year. Efforts to produce green NH are compromised since it is difficult to separate using conventional condensation chillers, but in situ separation with minimal cooling is challenging. While metal-organic framework materials offer some potential, they are often unstable and decompose in the presence of caustic and corrosive NH.
View Article and Find Full Text PDFUnderstanding the nature of intermediates/active species in reactions is a major challenge in chemistry. This is because spectator species typically dominate the experimentally derived data and consequently active phase contributions are masked. Transient methods offer a means to bypass this difficulty.
View Article and Find Full Text PDFModifying traditional Co/TiO-based Fischer-Tropsch (FT) catalysts with Mn promoters induces a selectivity shift from long-chain paraffins toward commercially desirable alcohols and olefins. In this work, we use gas cell scanning transmission electron microscopy (STEM) with energy-dispersive X-ray spectroscopy (EDS) elemental mapping, and near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) to demonstrate how the elemental dispersion and chemical structure of the as-calcined materials evolve during the H activation heat treatment required for industrial CoMn/TiO FT catalysts. We find that Mn additions reduce both the mean Co particle diameter and the size distribution but that the Mn remains dispersed on the support after the activation step.
View Article and Find Full Text PDFDecubitus ulcers, also known as bed ulcers or pressure ulcers, result from prolonged pressure on the skin, with contributing factors such as shear forces, friction and excessive moisture. Pressure ulcers have significant physical, social and psychological consequences for patients and impose a substantial financial burden on healthcare providers. Patient and caregiver education has been suggested as a potential approach for preventing pressure ulcers.
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