Spanish National Research Council

About: Spanish National Research Council is a government organization based out in Madrid, Spain. It is known for research contribution in the topics: Population & Galaxy. The organization has 79563 authors who have published 220470 publications receiving 7698991 citations. The organization is also known as: CSIC & Consejo Superior de Investigaciones Científicas.

Oxidative dehydrogenation of lower alkanes on vanadium oxide-based catalysts. The present state of the art and outlooks

Abstract: This review summarizes published data on catalytic performances of different vanadium-containing oxides, including unsupported and supported V2O5, vanadates, solid solutions and mixed phases, in the oxidative dehydrogenation of C2–C5 alkanes. The analysis of the structure-activity relationships shows that various species characterized by a different reactivity exist on the surface of these catalysts. There are some indications that tetrahedral vanadium species are the most favourable for alkane oxidehydrogenation. Its intrinsic activity seems to be largely dependent on the structure of the nearest surrounding and, therefore, can be modified by changing the nature and number of the neighbouring ions. Although the reaction mechanism is generally accepted to be through the redox cycle between V5+ and V4+, opposite relationships between catalyst activity/selectivity and reducibility have been established, even for the same catalytic systems. No clear interpretation regarding the mode of alkane activation can be derived from a survey of the literature. This and some other aspects of the reaction mechanism need further studies at a molecular level.

Periodically Rippled Graphene: Growth and Spatially Resolved Electronic Structure

Abstract: We grow epitaxial graphene monolayers on Ru(0001) that cover uniformly the substrate over lateral distances larger than several microns. The weakly coupled graphene monolayer is periodically rippled and it shows charge inhomogeneities in the charge distribution. Real space measurements by scanning tunneling spectroscopy reveal the existence of electron pockets at the higher parts of the ripples, as predicted by a simple theoretical model. We also visualize the geometric and electronic structure of edges of graphene nanoislands.

A nanoporous molecular magnet with reversible solvent-induced mechanical and magnetic properties

Abstract: A nanoporous molecular magnet with reversible solvent-induced mechanical and magnetic properties

The genome of melon (Cucumis melo L.)

Abstract: We report the genome sequence of melon, an important horticultural crop worldwide. We assembled 375 Mb of the double-haploid line DHL92, representing 83.3% of the estimated melon genome. We predicted 27,427 protein-coding genes, which we analyzed by reconstructing 22,218 phylogenetic trees, allowing mapping of the orthology and paralogy relationships of sequenced plant genomes. We observed the absence of recent whole-genome duplications in the melon lineage since the ancient eudicot triplication, and our data suggest that transposon amplification may in part explain the increased size of the melon genome compared with the close relative cucumber. A low number of nucleotide-binding site–leucine-rich repeat disease resistance genes were annotated, suggesting the existence of specific defense mechanisms in this species. The DHL92 genome was compared with that of its parental lines allowing the quantification of sequence variability in the species. The use of the genome sequence in future investigations will facilitate the understanding of evolution of cucurbits and the improvement of breeding strategies.