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Curcumin, a chemical compound present in the well-known Indian spice turmeric, has uses in many different fields ranging from
medicinal chemistry to the dye industry. Its poor water solubility, though, makes Curcumin difficult to handle, making it
less appealing for potential uses. The principal aim of this work is to perform a computational study of the structural and
electronic properties of Curcumin {IUPAC name: 1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione} in several solvents,
and a comparison with experimental data. Rotameric equilibria, vibrational and thermochemical analysis, and electronic absorption
spectra (with ab initio and semi-empirical methodologies) have been studied, both in vacuum and in three selected solvents. Different computational
techniques have been applied and the results compared. Combined approaches resulted in very satisfactory results. Interesting
results have emerged, which suggest subsequent investigations about the nature of the excited states and potential derivatives
of Curcumin that possibly have non-linear optical applications, as a π-core for innovative materials in laser engineering and photonics. 相似文献
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Sabrina Brait Stefano Deabate Selby A. R. Knox Enrico Sappa 《Journal of Cluster Science》2001,12(1):139-173
A survey of the synthetic pathways and of the reactivity and catalytic activity of transition metal carbonyl clusters substituted with benzyne (and, for comparison, benzene and diene) ligands is given. Cluster-surface analogies are helpful in gaining an understanding of the homogeneous and heterogeneous catalytic behaviour of the clusters. 相似文献
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Emanuele Casini Enrico Miglierina Łukasz Piasecki Libor Veselý 《Israel Journal of Mathematics》2016,216(1):355-369
We present a Lindenstrauss space with an extreme point that does not contain a subspace linearly isometric to c. This example disproves a result stated by Zippin in a paper published in 1969 and it shows that some classical characterizations of polyhedral Lindenstrauss spaces, based on Zippin’s result, are false, whereas some others remain unproven; then we provide a correct proof for those characterizations. Finally, we also disprove a characterization of polyhedral Lindenstrauss spaces given by Lazar, in terms of the compact norm-preserving extension of compact operators, and we give an equivalent condition for a Banach space X to satisfy this property. 相似文献