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1.
Tom Van Puyenbroeck Valentina Montalto Michaela Saisana 《European Journal of Operational Research》2021,288(2):584-597
Culture is an integral part of a city's quality of life, a driver of urban change, and a genuine economic sector. To support benchmarking of urban culture and facilitate peer learning amongst policymakers, the European Commission has recently created the ‘Cultural and Creative Cities Index’. While this index builds on a standardised method to aggregate 29 indicators for the 155 selected cities, it is explicitly acknowledged that a ‘gold standard’ for a ‘Cultural and Creative City’ does not exist. Instead, different approaches should be allowed for in capturing cities’ cultural and creative vitality. This is the point of departure for this paper, which employs a Benefit-of-the-Doubt (BoD) modelling approach to allow cities to combine such respect for performance diversity with peer learning and benchmarking. Expert-based weights are used to provide expert-consistent bounds for the shares of key dimensions in a city's final BoD index value. We identify three city clusters, amongst which there are large performance differences. Accordingly, we focus on the within-group identification of peer cities and target values, which we illustrate in more detail for Bilbao, Krak?w and Umeå, towards the formulation of fit-for-purpose policy measures that can support culture-led development. 相似文献
2.
Russian Journal of Applied Chemistry - Industrial by product dumped from iron making industry (slag) has been modified by various chemical agents, particularly, paraffin wax, liquid nitrile... 相似文献
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XPS and resistive studies on thin films of a copper(II)‐based coordination polymer deposited on functionalized interdigital electrodes 下载免费PDF全文
Michael Günthel Jörg Hübscher Rosemarie Dittrich Edwin Weber Yvonne Joseph Florian Mertens 《Journal of Polymer Science.Polymer Physics》2015,53(5):335-344
A symmetrical 2‐thiopyrimidine based molecule with an expanded π‐electron system is synthesized and used to form a self‐assembled monolayer (SAM) on gold surfaces. Utilizing chemical vapor deposition a monolayer of (3‐mercaptopropyl)triethoxysilane is formed on silicon dioxide substrates. Both of these SAM coated substrates are characterized by X‐ray photoelectron spectroscopy and the growth of a coordination polymer built up from 5,5′‐(ethyne‐1,2‐diyl)bis(2‐hydroxyacetophenone) and copper(II) on dual SAM coated transducers is studied. After the deposition procedure on interdigital electrodes the electrical properties of the polymer are investigated performing resistive measurements. A significant change of the resistance, which depends on the surrounding atmosphere, proves the sensing behavior of the synthesized coordination polymer. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 335–344 相似文献
5.
David M. Koshy Dr. Shucheng Chen Dr. Dong Un Lee Dr. Michaela Burke Stevens Ahmed M. Abdellah Samuel M. Dull Gan Chen Dr. Dennis Nordlund Dr. Alessandro Gallo Dr. Christopher Hahn Dr. Drew C. Higgins Dr. Zhenan Bao Dr. Thomas F. Jaramillo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(10):4072-4079
Ni,N-doped carbon catalysts have shown promising catalytic performance for CO2 electroreduction (CO2R) to CO; this activity has often been attributed to the presence of nitrogen-coordinated, single Ni atom active sites. However, experimentally confirming Ni−N bonding and correlating CO2 reduction (CO2R) activity to these species has remained a fundamental challenge. We synthesized polyacrylonitrile-derived Ni,N-doped carbon electrocatalysts (Ni-PACN) with a range of pyrolysis temperatures and Ni loadings and correlated their electrochemical activity with extensive physiochemical characterization to rigorously address the origin of activity in these materials. We found that the CO2R to CO partial current density increased with increased Ni content before plateauing at 2 wt % which suggests a dispersed Ni active site. These dispersed active sites were investigated by hard and soft X-ray spectroscopy, which revealed that pyrrolic nitrogen ligands selectively bind Ni atoms in a distorted square-planar geometry that strongly resembles the active sites of molecular metal–porphyrin catalysts. 相似文献
6.
Stepwise Halide‐Triggered Double and Triple Catenation of Self‐Assembled Coordination Cages 下载免费PDF全文
Rongmei Zhu Jens Lübben Priv.‐Doz. Dr. Birger Dittrich Prof. Dr. Guido H. Clever 《Angewandte Chemie (International ed. in English)》2015,54(9):2796-2800
A simple self‐assembled [Pd2 L 4] coordination cage consisting of four carbazole‐based ligands was found to dimerize into the interpenetrated double cage [3 X@Pd4 L 8] upon the addition of 1.5 equivalents of halide anions (X=Cl?, Br?). The halide anions serve as templates, as they are sandwiched by four PdII cations and occupy the three pockets of the entangled cage structure. The subsequent addition of larger amounts of the same halide triggers another structural conversion, now yielding a triply catenated link structure in which each PdII node is trans‐coordinated by two pyridine donors and two halide ligands. This simple system demonstrates how molecular complexity can increase upon a gradual change of the relative concentrations of reaction partners that are able to serve different structural roles. 相似文献
7.
Late‐Stage Peptide Diversification by Bioorthogonal Catalytic CH Arylation at 23 °C in H2O 下载免费PDF全文
Dr. Yingjun Zhu Michaela Bauer Prof. Dr. Lutz Ackermann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(28):9980-9983
The step‐economical late‐stage diversification of tryptophan‐containing peptides was accomplished through chemo‐ and site‐selective palladium‐catalyzed C?H arylation under exceedingly mild reaction conditions. Thus, the C?H functionalization occurred efficiently at 23 °C with a catalyst loading as low as 0.5 mol %, and/or in H2O. 相似文献
8.
Arumugam Thangavel Marika Wieliczko Christopher Scarborough Birger Dittrich John Bacsa 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(11):936-943
In the crystal structure of the title homoleptic CrII complex, [Cr(CH3CN)6](C24H20B)2·CH3CN, the [Cr(CH3CN)6]2+ cation is a high‐spin d4 complex with strong static, rather than dynamic, Jahn–Teller distortion. The electron density of the cation was determined by single‐crystal X‐ray refinements using aspherical structure factors from wavefunction calculations. The detailed picture of the electronic density allowed us to assess the extent and directionality of the Jahn–Teller distortion of the CrII cation away from idealized octahedral symmetry. The topological analysis of the aspherical d‐electron density about the CrII cation showed that there are significant valence charge concentrations along the axial Cr—N axes. Likewise, there were significant valence charge depletions about the CrII cation along the equatorial Cr—N bonds. These charge concentrations are in accordance with a Jahn–Teller‐distorted six‐coordinate complex. 相似文献
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Michaela Dobeneck Ramandeep Kaur Benedikt Platzer Prof. Dr. Dirk M. Guldi Prof. Dr. Andreas Hirsch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(32):8325-8336
A modified synthetic pathway towards perylene-perylene dimers and a facile purification method to obtain the regioisomerically pure syn- and anti-isomers are reported. In addition, a novel perylene-naphthalene heterodimer with 30 conjugated π-electron pairs was designed and synthesized on the basis of a previously described precursor and the resulting regioisomers were separated from each other. Thereby, the opto-electronic properties of the linearly elongated chromophores could be investigated regarding the differences in length of their aromatic system and the configuration of the isomers. Further tuning of their energy gaps was realized via protonation and methylation of the dibenzimidazole-bridging unit. Extraordinary red-shifts of the absorption maxima of 62 nm for the methylated and 92 nm for the protonated perylene-perylene anti-isomer could be achieved. Moreover, the maxima for the syn-isomer could be shifted bathochromically by 87 and 113 nm, respectively. 相似文献