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Surface of High-Entropy perovskite catalyst La(CoCuFeAlCe)0.2O3 (100) : Experimental study of methanol steam reforming for hydrogen production and DFT mechanism research

High-entropy perovskite catalyst was synthesized and utilized for the first time in the MSR catalytic reaction. Among the HEPs, La(CoCuFeAlCe)0.2O3 exhibited excellent MSR activity and high selectivity. The mechanism of the MSR reaction on the catalyst (100) surface was studied by employing DFT. The results indicate that the surface of La(CoCuFeAlCe)0.2O3 catalyst has the lowest energy barrier, wh

Exploring the potential of perovskite LaBO3 (B = Co, Fe, Cu, Al) as an efficient and durable hydrogen production catalyst for methanol steam reforming : Experimental and DFT studies

In this study, LaBO3 (B = Co, Fe, Cu, Al) perovskite catalysts were introduced for Methanol Steam Reforming (MSR). Results showed that LaCoO3 displayed a 100 % methanol conversion efficiency and a notable hydrogen production rate of 7.86 mol/min/gcat, maintaining stability for more than 40 h at 600 °C. Theoretical computations indicate that the CH3O dehydrogenation to CH2O (a rate-determining proc

Climate variability and anthropogenic impacts through a palaeo-morphological lens: an innovative microCT approach using Baltic Sea benthic foraminifera

Human-induced impacts are increasing pressure on coastal ecosystems, particularly on benthic ecosystems in high-latitude regions. It has become evident that three of the greatest marine environmental challenges related to anthropogenic activity are warming, ocean acidification, and deoxygenation. The effect of these environmental changes on our uncertain future has created a need to understand the

Effect of substrate misorientation angle on the structural properties of N-polar GaN grown by hot-wall MOCVD on 4H-SiC(0001̄)

The effects of substrate misorientation angle direction and degree on the structural properties of N-polar GaN grown by a novel multi-step temperature epitaxial approach using hot-wall metal–organic chemical vapor deposition (MOCVD) on 4H-SiC (0001̄) substrates is investigated. The surface morphology and X-ray diffraction (XRD) rocking curves (RCs) for both symmetric and asymmetric Bragg peaks of

The “gut” corona at the surface of nanoparticles is dependent on exposure to bile salts and phospholipids

Hypothesis: The formation of a biomolecular corona on nanoparticle surfaces significantly influences their biological behaviour, particularly in drug delivery applications. Despite the prevalence of ingestion of particles (e.g, during oral drug delivery), our understanding of corona formation within the gastrointestinal (GI) tract remains limited, especially for non-protein components. The hypothe

Tribological behavior and wear particle emission influenced by surface conditions of cast iron discs

Hard coatings can be applied to a traditional cast iron brake disc to increase wear resistance and thus reduce brake disc particle emission. An alumina coating prepared through a modified plasma electrolytic oxidation (PEO) process also shows a promise in wear reduction for automotive brake disc. The aim of the work was further to study effect of the alumina coating surface conditions on tribologi

Lo-Fi Prototyping a Refreshable Pin Display

This paper presents a way of creating and working with lo-fi materials for a tactile refreshable pin display. The materials were seen to work well, and supported co-design discussions around the future design of, and interaction with, the – as yet, non-existing – tactile device.

Void formation driven by plastic strain partitioning during creep deformation of WC-Co

Creep deformation of WC-Co composites at high temperature and stress is accommodated by either bulk WC creep or by Co-infiltrated grain boundary sliding. It has been proposed that certain grain boundaries are more susceptible than others to such sliding, and depending on the applied stress, the overall deformation rate can be limited by either mechanism. Here, we have used Electron Back-Scatter Di

Performance and wear mechanisms of TiAlN-NbN coated cemented carbide in milling Ti6Al4V with different cooling and lubrication approaches

Titanium alloys are difficult-to-machine materials given their high strength, the high temperatures generated, and the naturally short contact length that combined result in rapid tool wear. Different machining strategies can be employed to cope with the low machinability. This study investigates the machining performance using different cooling and lubrication methods during down face milling of

Ontology-based integration and querying of heterogeneous rare disease data sources — POLVAS perspective

The integration of rare disease medical databases belonging to different countries is an important problem, as a large number of observations are required for reliable statistical inference of patient data in order to facilitate clinical research. Such integration of national registry data, which requires harmonization of the heterogeneous data sets into a unified view, is facilitated in the Europ

Deglacial history of the Kattegat-Baltic Sea using x-ray micro-computed tomography of benthic foraminifera

The Baltic Sea is strongly affected by the combined stressors of deoxygenation, acidification, and eutrophication. These are primarily derived from 1) anthropogenic CO2 emissions, which increase atmospheric temperatures, enhance surface water stratification, reduce oxygen solubility, and alter carbonate chemistry, and 2) nutrient pollution from the Baltic Sea’s heavily populated coastline. Togethe

EuPPollNet : A European Database of Plant-Pollinator Networks

Motivation: Pollinators play a crucial role in maintaining Earth's terrestrial biodiversity. However, rapid human-induced environmental changes are compromising the long-term persistence of plant-pollinator interactions. Unfortunately, we lack robust, generalisable data capturing how plant-pollinator communities are structured across space and time. Here, we present the EuPPollNet (European Plant-

The neuroethology of ant navigation

Unlike any other group of animals, all ant species are social: individual ants share the food they gather with their nestmates and as a consequence they must repeatedly leave their nest to find food and then return home with it. These back-and-forth foraging trips have been studied for about a century and much of our growing understanding of the strategies underlying animal navigation has come fro

Exploring relationships between time of day and pollinator activity in the context of pesticide use

Pesticide exposure can be harmful to insect pollinators and the ecosystem services they provide. As many pesticide guidelines warn against applying such products when pollinators are active, it is important to evaluate how pollinator activity changes with time of day to determine the most appropriate time to spray.We walked transects from sunrise to sunset in oilseed rape (Brassica napus L.) field

Fusion cross section of superheavy elements using a Markov chain method

De allra tyngsta grundämnena i det periodiska systemet är skapade genom att man skjuter in en lätt atom in i en annan, tyngre, atom för att de ska slås ihop och skapa än ännu tyngre atom. Denna processen kallas fusion. Fusion är samma fenomen som driver solen genom sammanslagningen av väte till helium. För att uppnå fusion måste atomerna först övervinna den s.k. Coulombbarriären, den frånstötande This thesis models fusion reactions for the production of superheavy elements using a fusion by diusion model. The work further develops the diusion model in Ref. [1], achieving signicant computational speedup. In the diffusion model, I demonstrate that the use of a Markov chain method in place of a Langevin random walk method decreases computational time signicantly, by at least two orders of mag