Search results for "ATAL"
showing 10 items of 10591 documents
Effect of atomic layer deposited zinc promoter on the activity of copper-on-zirconia catalysts in the hydrogenation of carbon dioxide to methanol
2023
Funding Information: The work at Aalto University has been financially supported by the Academy of Finland (COOLCAT consortium, decision no. 329977 and 329978 ; ALDI consortium, decision no. 331082 ). This work made use of Aalto University Bioeconomy, OtaNano and RawMatters infrastructure. Hannu Revitzer (Aalto University) is thanked for the ICP-OES analysis, Aalto workshop people (especially Seppo Jääskeläinen) for working on the reactor modifications. The DFT calculations were made possible by computational resources provided by the CSC — IT Center for Science, Espoo, Finland ( https://www.csc.fi/en/ ) and computer capacity from the Finnish Grid and Cloud Infrastructure (urn:nbn:fi:resear…
Water-use efficiency and transpiration across European forests during the Anthropocene
2015
Considering the combined effects of CO2 fertilization and climate change drivers on plant physiology leads to a modest increase in simulated European forest transpiration in spite of the effects of CO2-induced stomatal closure. The Earth’s carbon and hydrologic cycles are intimately coupled by gas exchange through plant stomata1,2,3. However, uncertainties in the magnitude4,5,6 and consequences7,8 of the physiological responses9,10 of plants to elevated CO2 in natural environments hinders modelling of terrestrial water cycling and carbon storage11. Here we use annually resolved long-term δ13C tree-ring measurements across a European forest network to reconstruct the physiologically driven r…
Comment on “Crystallographic Snapshot of an Arrested Intermediate in the Biomimetic Activation of CO2”
2015
Out of focus: A recent Communication published in this journal describes the synthesis of [nBu4 N]HCO3 . The authors performed a single-crystal X-ray study that revealed a putative species described as an incipient hydroxide ion engaging in a long, and presumably weak, interaction with CO2 . Our recent exploration of the coordination chemistry of CO2 with small ions leads us to believe that such an exceptional bonding situation is unlikely. Instead, we argue that the crystal structure is that of [nBu4 N]O2 CCH3 and therefore not representative of the bulk powder from the synthesis.
Influence of a Cu–zirconia interface structure on CO2 adsorption and activation
2021
CO2 adsorption and activation on a catalyst are key elementary steps for CO2 conversion to various valuable products. In the present computational study, we screened different Cu–ZrO2 interface structures and analyzed the influence of the interface structure on CO2 binding strength using density functional theory calculations. Our results demonstrate that a Cu nanorod favors one position on both tetragonal and monoclinic ZrO2 surfaces, where the bottom Cu atoms are placed close to the lattice oxygens. In agreement with previous calculations, we find that CO2 prefers a bent bidentate configuration at the Cu–ZrO2 interface and the molecule is clearly activated being negatively charged. Strain…
Exploring CO2 hydrogenation to methanol at a CuZn–ZrO2 interface via DFT calculations
2023
Multi-component heterogeneous catalysts are among the top candidates for converting greenhouse gases into valuable compounds. Combinations of Cu, Zn, and ZrO2 (CZZ) have emerged as promisingly efficient catalysts for CO2 hydrogenation to methanol. To explore the catalytic mechanism, density functional theory (DFT) calculations and the energetic span model (ESM) were used to study CO2 conversion routes to methanol on CuZn–ZrO2 interfaces with a varying Zn content. Our results demonstrate that the presence of Zn sites at the interface improves CO2 binding. However, the adsorption and activation energies are insensitive to Zn concentration. The calculations also show that the hydrogenation of …
Prenatal Exposure to Δ9-Tetrahydrocannabinol Affects Hippocampus-Related Cognitive Functions in the Adolescent Rat Offspring: Focus on Specific Marke…
2023
Previous evidence suggests that prenatal exposure to THC (pTHC) derails the neurodevelopmental trajectories towards a vulnerable phenotype for impaired emotional regulation and limbic memory. Here we aimed to investigate pTHC effect on hippocampus-related cognitive functions and markers of neuroplasticity in adolescent male offspring. Wistar rats were exposed to THC (2 mg/kg) from gestational day 5 to 20 and tested for spatial memory, object recognition memory and reversal learning in the reinforce-motivated Can test and in the aversion-driven Barnes maze test; locomotor activity and exploration, anxiety-like behaviour, and response to natural reward were assessed in the open field, elevate…
Las versiones castellanas medievales de la Consolatio Philosophiae de Boecio
2016
Boecio fue uno de los autores más influyentes en la Baja Edad Media hispánica. Su obra más importante, la Consolatio Philosophiae, fue el texto traducido en más ocasiones, el segundo en número de manuscritos vernáculos conservados y la obra de la Antigüedad con mayor número de impresiones en época incunable. La nómina de autores que se sirvieron de la Consolatio como fuente directa o influencia clave en cuanto a forma o contenido incluye a los más destacados escritores de la literatura catalana y castellana; es, además, una presencia inexcusable en algunos de los géneros más populares en la literatura cuatrocentista, como los tratados sobre predestinación, fortuna y libre albedrío, los trat…
Reconstrucció del paisatge rural i urbà d'Almenara i La Llosa entre els segle XIII al XVI
2023
La tesi titulada «Reconstrucció del paisatge rural i urbà d'Almenara i La Llosa entre els segles XIII-XVI», aprofundeix en l'evolució del paisatge cultural d'ambdós municipis i l'estudi de la seua població. Amb la finalitat de valorar els béns culturals municipals d'aquest període i destacar-ne la rellevància i les funcions en el passat. Cosa que possibilita una millor acceptació en el manteniment i en el respecte d'aquests béns en la societat actual. El paisatge constitueix una realitat dinàmica, ja que és resultat de processos ambientals, socials i culturals que s'han succeït al llarg del temps en el territori. Aquests processos estan marcats per les maneres de vida, les polítiques, les a…
El model lèxic culte de Constantí Llombart
2020
En aquest article s’estudia el model lèxic culte de Constantí Llombart, un dels principals representants de la Renaixença valenciana. Llombart pretenia fer extensiu aquest moviment de recuperació cultural a tots els sectors de la societat valenciana, i, per això va assajar per a la llengua literària un model lingüístic de síntesi, que evitàs les formes considerades vulgars i castellanitzants de la llengua col·loquial, però també els arcaismes que poguessen distanciar-lo dels sectors populars. En la depuració lèxica de la llengua literària, Llombart tingué en compte els clàssics i els escriptors renaixentistes de Catalunya, on creia que el moviment de recuperació cultural estava més consolid…
Recognition of alkali metal halide contact ion pairs by uranyl-salophen receptors bearing aromatic sidearms. The role of cation-pi interactions.
2005
Hard anions have long been known to bind strongly to the uranium of uranyl-salophen complexes. Upon functionalization of the salophen framework with one or two benzyloxy substituents, efficient ditopic receptors for alkali metal ions are obtained. The solid-state structures of complexes formed by the two-armed receptor 1 with CsF and with the chlorides of K+, Rb+, and Cs+ reported here reveal the existence of dimeric supramolecular assemblies in which two receptor units assemble into capsules fully enclosing (MX)2 ion quartets. In addition to the strong coordinative binding of the anion to the uranyl center and to electrostatic cation-anion interactions, stabilizing interactions arise from …