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221.
Sidney F. A. Kettle Eliano Diana Edoardo M. C. Marchese Enrico Boccaleri Pier Luigi Stanghellini 《Journal of Raman spectroscopy : JRS》2011,42(11):2006-2014
A careful analysis of the Raman spectra of the M′x[M(CN)6]y Prussian blue species has enabled a general model for the interpretation of the ν(CN) vibrational spectra. The spectral patterns are derived from those of the metal ions with local Oh symmetry. Two limiting models are discussed. A ‘localized mode’ model, involving matrix‐isolated species, is in much better accord with the observations than a ‘factor group’ model. The use of the infrared feature as fingerprint of specific M CN M′ units arises from the axis‐specific nature of individual T1u modes. The interpretation of the A1g and Eg Raman features is done in terms of localized vibrations, with involvement of additional energy terms from the lattice motions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Enrico Falcone Ikhlas M. M. Ahmed Dr. Valentina Oliveri Dr. Francesco Bellia Dr. Bertrand Vileno Dr. Youssef El Khoury Prof. Petra Hellwig Prof. Peter Faller Prof. Graziella Vecchio 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(8):1871-1879
Mounting evidence supports the role of amyloidogenesis, oxidative stress, and metal dyshomeostasis in the development of neurodegenerative disorders. Parkinson's Disease is characterized by α-synuclein (αSyn) accumulation and aggregation in brain regions, also promoted by Cu2+. αSyn is modified by reactive carbonyl species, including acrolein (ACR). Notwithstanding these findings, the interplay between ACR, copper, and αSyn has never been investigated. Therefore, we explored more thoroughly the effects of ACR on αSyn using an approach based on LC-MS/MS analysis. We also evaluated the influence of Cu2+ on the protein carbonylation and how the ACR modification impacts the Cu2+ binding and the production of Reactive Oxygen Species (ROS). Finally, we investigated the effects of ACR and Cu2+ ions on the αSyn aggregation by dynamic light scattering and fluorescence assays. Cu2+ regioselectively inhibits the modification of His50 by ACR, the carbonylation lowers the affinity of His50 for Cu2+ and ACR inhibits αSyn aggregation both in the presence and in the absence of Cu2+. 相似文献
224.
Coclite Giuseppe Maria Dipierro Serena Maddalena Francesco Valdinoci Enrico 《Journal of Nonlinear Science》2020,30(4):1285-1305
The formation of singularities in finite time in nonlocal Burgers’ equations, with time-fractional derivative, is studied in detail. The occurrence of finite-time singularity is proved, revealing the underlying mechanism, and precise estimates on the blowup time are provided. The employment of the present equation to model a problem arising in job market is also analyzed.
相似文献225.
Post‐Synthetic Ligand Exchange in Zirconium‐Based Metal–Organic Frameworks: Beware of The Defects!
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Dr. Marco Taddei Dr. Russell J. Wakeham Athanasios Koutsianos Dr. Enrico Andreoli Prof. Andrew R. Barron 《Angewandte Chemie (International ed. in English)》2018,57(36):11706-11710
Post‐synthetic ligand exchange in the prototypical zirconium‐based metal–organic framework (MOF) UiO‐66 was investigated by in situ solution 1H NMR spectroscopy. Samples of UiO‐66 having different degrees of defectivity were exchanged using solutions of several terephthalic acid analogues in a range of conditions. Linker exchange only occurred in defect‐free UiO‐66, whereas monocarboxylates grafted at defect sites were found to be preferentially exchanged with respect to terephthalic acid over the whole range of conditions investigated. A 1:1 exchange ratio between the terephthalic acid analogue and modulator was observed, providing evidence that the defects had missing‐cluster nature. Ex situ characterisation of the MOF powders after exchange corroborated these findings and showed that the physical‐chemical properties of the MOF depend on whether the functionalisation occurs at defective sites or on the framework. 相似文献
226.
Enrico Rogora 《Geometriae Dedicata》1997,64(2):157-191
In this paper I give a classification of irreducible projective varieties of dimension less than or equal to four, according to a new classification scheme. No assumption is made about singularities. 相似文献
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Symmetrization and norm of the Hardy-Littlewood maximal operator on Lorentz and Marcinkiewicz spaces
Colzani Leonardo; Laeng Enrico; Morpurgo Carlo 《Journal London Mathematical Society》2008,77(2):349-362
We prove that when a function on the real line is symmetricallyrearranged, the distribution function of its uncentered Hardy–Littlewoodmaximal function increases pointwise, while it remains unchangedonly when the function is already symmetric. Equivalently, if is the maximal operator and the symmetrization, then f(x)f(x)for every x, and equality holds for all x if and only if, upto translations, f(x) = f(x) almost everywhere. Using theseresults, we then compute the exact norms of the maximal operatoracting on Lorentz and Marcinkiewicz spaces, and we determineextremal functions that realize these norms. 相似文献
229.
Biavardi E Battistini G Montalti M Yebeutchou RM Prodi L Dalcanale E 《Chemical communications (Cambridge, England)》2008,(14):1638-1640
We report here the monitoring of reversible guest inclusion in phosphonate cavitands through a large increase in luminescence intensity caused by the modulation of the exoergonicity of an electron-transfer reaction. 相似文献
230.