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Srgio R. Domingos Kvin Martin Narcis Avarvari Melanie Schnell 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(33):11379-11383
We report on the one‐ and two‐water clusters of [4]helicene, the smallest polycyclic aromatic hydrocarbon with a helical sense, which were captured in the gas phase using high‐resolution rotational spectroscopy. The structures of the complexes are unambiguously revealed using microwave spectra of isotopically enriched species. In the one‐water cluster, the apparent splitting pattern is consistent with a tunneling motion that encompasses an exchange of strongly and weakly bonded water hydrogens. This motion is “locked” in the two‐water cluster. The relevant intermolecular contacts, symmetry, and aromaticity effects are unveiled for the microsolvated chiral topologies. These observations entail the first glance at the structures and internal dynamics of the water binding motifs of a chiral polycyclic aromatic hydrocarbon. 相似文献
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Stieghorst Christian Hampel Gabriele Karches Barbara Krenckel Patricia Kudějová Petra Plonka Christian Révay Zsolt Riepe Stephan Welter Katharina Wiehl Norbert 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):307-313
Journal of Radioanalytical and Nuclear Chemistry - For the optimization of the manufacturing process of multicrystalline silicon (mc-Si) for solar cells in order to reduce energy consumption and... 相似文献
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Nathan Barker Nigel Boston Norbert Peyerimhoff Alina Vdovina 《Monatshefte für Mathematik》2012,3(2):319-327
We find new mixed and unmixed Beauville structures for groups constructed as 2-quotients, i.e. quotients of 2-power order, of the fundamental group of a certain simplicial complex. 相似文献
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Dominik Lungerich Jakob F. Hitzenberger Wolfgang Donaubauer Prof. Thomas Drewello Prof. Norbert Jux 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(47):16755-16759
A feasible two‐step synthesis and characterization of a full series of hexaarylbenzene (HAB) substituted porphyrins and tetrabenzoporphyrins is presented. Key steps represent the microwave‐assisted porphyrin condensation and the statistical Diels–Alder reaction to the desired HAB‐porphyrins. Regarding their applications, they proved to be easily accessible and effective high molecular mass calibrants for (MA)LDI mass spectrometry. The free‐base and zinc(II) porphyrin systems, as well as the respective tetrabenzoporphyrins, demonstrate in solid state experiments strong red‐ and near‐infrared‐light emission and are potentially interesting for the application in “truly organic” light‐emitting devices. Lastly, they represent facile precursors to large polycyclic aromatic hydrocarbon (PAH) substituted porphyrins. We prepared the first tetra‐hexa‐peri‐hexabenzocoronene substituted porphyrin, which represents the largest prepared PAH‐porphyrin conjugate to date. 相似文献
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Jieping Wang Norbert Moszner Kurt Dietliker Hansjörg Grützmacher Robert Liska 《Journal of polymer science. Part A, Polymer chemistry》2016,54(4):473-479
The monoacylphosphineoxide (MAPO) salts Na‐TPO and Li‐TPO and the bisacylphosphineoxide (BAPO) salts BAPO‐ONa and BAPO‐OLi define an important and in the latter case a new class of water‐soluble photoinitiators (PIs) for radical polymerization. These compounds showed excellent water‐solubility of at least 29 g/L for Na‐TPO and up to 60 g/L for BAPO‐ONa in deionized water, thus exceeding the solubility of the state of the art PI for water‐based systems Irgacure 2959 ( I2959 ) 6‐ to 12‐fold. However, biocompatibility, storage stability, and reactivity were equally important to replace the state of the art compounds. Concerning these properties, the MAPO and BAPO salts were at least in the same range (biocompatibility, stability) or showed even better results (reactivity) and had the additional advantage of visible light initiation. Na‐TPO and Li‐TPO achieved double bond conversions of an aqueous solution of N‐acryloylmorpholine over 97% with broad band irradiation (320–500 nm), Li‐TPO showed additionally very good biocompatibility (LC50 = 3.1 mmol/L) and BAPO‐OLi showed highest reactivity with visible light irradiation. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 473–479 相似文献