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291.
Universal Access in the Information Society - 相似文献
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R. Pereñíguez J. L. Hueso F. Gaillard J. P. Holgado A. Caballero 《Catalysis Letters》2012,142(4):408-416
Abstract
The total oxidation of toluene is studied over catalytic systems based on perovskite with general formula AA′CoO3-δ (A = La, A′ = Sr). The systematic and progressive substitution of La3+ by Sr2+ cations in the series (La1−x Sr x CoO3−δ system) of the perovskites have been studied to determine their influence in the final properties of these mixed oxides and their corresponding reactivity performance for the total oxidation of toluene as a model volatile organic compound with detrimental effects for health and environment. The structure and morphology of the samples before and after reaction have been characterized by XRD, BET and FE-SEM techniques. Additional experiments of temperature programmed desorption of O2 in vacuum and reduction in H2 were also performed to identify the main surface oxygen species and the reducibility of the different perovskites. It is remarkable that the La1−x Sr x CoO3−δ series presents better catalytic performance for the oxidation of toluene, with lower values for the T50 (temperature of 50 % toluene conversion) than the previously studied LaNi1−y Co y O3 series. 相似文献294.
Julia Hernandez-Baixauli Pere Puigb Nerea Abasolo Hector Palacios-Jordan Elisabet Foguet-Romero David Suol Mar Galofr Antoni Caimari Laura Baselga-Escudero Josep M. Del Bas Miquel Mulero 《International journal of molecular sciences》2021,22(23)
Stress disorders have dramatically increased in recent decades becoming the most prevalent psychiatric disorder in the United States and Europe. However, the diagnosis of stress disorders is currently based on symptom checklist and psychological questionnaires, thus making the identification of candidate biomarkers necessary to gain better insights into this pathology and its related metabolic alterations. Regarding the identification of potential biomarkers, omic profiling and metabolic footprint arise as promising approaches to recognize early biochemical changes in such disease and provide opportunities for the development of integrative candidate biomarkers. Here, we studied plasma and urine metabolites together with metagenomics in a 3 days Chronic Unpredictable Mild Stress (3d CUMS) animal approach that aims to focus on the early stress period of a well-established depression model. The multi-omics integration showed a profile composed by a signature of eight plasma metabolites, six urine metabolites and five microbes. Specifically, threonic acid, malic acid, alpha-ketoglutarate, succinic acid and cholesterol were proposed as key metabolites that could serve as key potential biomarkers in plasma metabolome of early stages of stress. Such findings targeted the threonic acid metabolism and the tricarboxylic acid (TCA) cycle as important pathways in early stress. Additionally, an increase in opportunistic microbes as virus of the Herpesvirales was observed in the microbiota as an effect of the primary stress stages. Our results provide an experimental biochemical characterization of the early stage of CUMS accompanied by a subsequent omic profiling and a metabolic footprinting that provide potential candidate biomarkers. 相似文献
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Carlos J. Moreno Samantha Gittings Dieter Schollmeyer Jesús Joglar Jordi Bujons Karel Hernández Pere Clapés 《Advanced Synthesis \u0026amp; Catalysis》2024,366(4):990-1000
Chiral 2-hydroxy-4-arylbut-3-enoic acid derivatives are important precursors for the synthesis of angiotensin converting enzyme (ACE) inhibitors, such as enalapril, lisinopril, cilapril or benazepril. In this work, we take advantage of the unexplored promiscuous ketoreductase activity of Δ1-piperidine-2-carboxylate/Δ1-pyrroline-2-carboxylate reductase from Pseudomonas syringae pv. tomato DSM 50315 (DpkAPsyrin) for the synthesis of (S,E)-2-hydroxy-4-arylbut-3-enoic acids. The strategy was designed as an enzymatic cascade comprising an aldol condensation between pyruvate with aryl aldehydes, catalyzed by the trans-o-hydroxybenzylidene pyruvate hydratase-aldolase from Pseudomonas putida (HBPAPputida), for the construction of carbon scaffold, and an ensuing asymmetric reduction of the carbonyl group catalyzed by DpkAPsyrin. The enzymatic cascade provided quantitative conversions, with global isolated yields between 57–85%. A total of nine structurally diverse (S,E)-2-hydroxy-4-arylbut-3-enoic acids were prepared in ee between 87–99%. 相似文献
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AbstractDue to the recent advances in robotics, large numbers of robots can be created that exhibit ‘swarm-like’ behavior. These robots, typically small and low-cost with restricted sensing, often exhibit Brownian motion similar to micro-particles. The development of algorithms that create collective behavior that is robust to external pressures has applications in outdoor exploration, search and rescue operations, and nanomedicine. Here, we outline how a swarm of minimal robots, exhibiting only Brownian motion and with limited sensing capabilities, can form trails using mechanisms inspired by diffusion-limited aggregation (DLA). We demonstrate how the trail is robust to obstacles and efficient at finding the closest target. We validate this algorithm both in simulation as well as in reality, using a swarm of up to 100 robots, and highlight the optimum requirements for trail formation. 相似文献
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Wireless Personal Communications - In this paper, we present a study on the performance of direct-oversampling correlator-type receivers in chaos-based direct-sequence code division multiple access... 相似文献
300.
Interpolation with restrictions between finite element meshes for flow problems in an ALE setting 下载免费PDF全文
Arnau Pont Ramon Codina Joan Baiges 《International journal for numerical methods in engineering》2017,110(13):1203-1226
The need for remeshing when computing flow problems in domains suffering large deformations has motivated the implementation of a tool that allows the proper transmission of information between finite element meshes. Because the Lagrangian projection of results from one mesh to another is a dissipative method, a new conservative interpolation method has been developed. A series of constraints, such as the conservation of mass or energy, are applied to the interpolated arrays through Lagrange multipliers in an error minimization problem, so that the resulting array satisfies these physical properties while staying as close as possible to the original interpolated values in the L2 norm. Unlike other conservative interpolation methods that require a considerable effort in mesh generation and modification, the proposed formulation is mesh independent and is only based on the physical properties of the field being interpolated. Moreover, the performed corrections are neither coupled with the main calculation nor with the interpolation itself, for which reason the computational cost is very low. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献