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Rudolf Gompper Jan-Gerd Hansel Joachim Hock Kurt Polborn Elmar Dormann Hubert Winter 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):521-525
Abstract Novel dithiolene metal complexes, some of which absorb in the near infrared, and tetrathiafulvalenes, in particular tetraiodotetrathia- fulvalene, have been prepared, and their magnetic properties studied. 相似文献
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David Falck Anna J. Oosthoek-de Vries Ard Kolkman Henk Lingeman Maarten Honing Sybren S. Wijmenga Arno P. M. Kentgens Wilfried M. A. Niessen 《Analytical and bioanalytical chemistry》2013,405(21):6711-6720
Flow-through electrochemical conversion (EC) of drug-like molecules was hyphenated to miniaturized nuclear magnetic resonance spectroscopy (NMR) via on-line solid-phase extraction (SPE). After EC of the prominent p38α mitogen-activated protein kinase inhibitor BIRB796 into its reactive products, the SPE step provided preconcentration of the EC products and solvent exchange for NMR analysis. The acquisition of NMR spectra of the mass-limited samples was achieved in a stripline probe with a detection volume of 150 nL offering superior mass sensitivity. This hyphenated EC–SPE–stripline-NMR setup enabled the detection of the reactive products using only minute amounts of substrate. Furthermore, the integration of conversion and detection into one flow setup counteracts incorrect assessments caused by the degradation of reactive products. However, apparent interferences of the NMR magnetic field with the EC, leading to a low product yield, so far demanded relatively long signal averaging. A critical assessment of what is and what is not (yet) possible with this approach is presented, for example in terms of structure elucidation and the estimation of concentrations. Additionally, promising routes for further improvement of EC–SPE–stripline-NMR are discussed. 相似文献
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Wilfried Hellebrandt Thomas Haselhorst Thies Köhli Englbert Bäuml Thomas Peters 《Journal of carbohydrate chemistry》2013,32(6):769-782
ABSTRACT NMR spectroscopic analysis of carbohydrates often suffers from severe overlap of resonance signals, especially in 1H NMR spectra. Therefore, we synthesized four 2,3,4-trideuterio-α-L-fucose containing disaccharides, α-L-Fuc-(1→6)-β-D-GlcNAc-OMe 1, α-L-Fuc-(1→4)-β-D-GlcNAc-OMe 2, α-L-Fuc-(1→3)-β-D-GlcNAc-OMe 3, and α-L-Fuc-(1→2)-β-D-Gal-OMe 4. Compounds 1 to 4 are well suited to be subjected to NMR conformational analysis because their 1H NMR spectra show almost no overlap of signals. The deuterated disaccharides 1 to 4 will therefore be used as NMR probes for the exploration of fucose-binding proteins. With a mixture of the corresponding non-deuterated disaccharides it is demonstrated that recently developed parallel NMR screening protocols, Bio-Affinity NMR and STD-NMR, deliver fast and robust tools to assay the compounds synthesized for protein-binding affinity. 相似文献
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Prof. Dr. Sjoerd Harder Dominik Naglav Dr. Christian Ruspic Prof. Dr. Claudia Wickleder Dr. Matthias Adlung Dr. Wilfried Hermes Dr. Matthias Eul Prof. Dr. Rainer Pöttgen Dr. Daniel B. Rego Prof. Dr. Frederic Poineau Prof. Dr. Kenneth R. Czerwinski Prof. Dr. Rolfe H. Herber Prof. Dr. Israel Nowik 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(37):12173-12173
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Gerda Rogl Viktor Soprunyuk Wilfried Schranz Michael J. Zehetbauer Jiri Bursik Herbert Müller Ernst Bauer Peter F. Rogl 《无机化学与普通化学杂志》2020,646(14):1267-1272
Thermoelectric materials with a high figure of merit, ZT, are the essential basis to build thermoelectric generators, which can directly convert heat into electricity. Severe plastic deformation (SPD) via high-pressure torsion (HPT) was successfully applied to enhance ZT of ball-milled and hot-pressed skutterudites as well as to produce bulk nanostructured skutterudites directly from powders. SPD introduces many defects into the sample and in parallel the crystallite size is significantly reduced. During measurement-induced heating these defects anneal partially out, and the grains grow. In this work for the first time systematically the changes of the temperature-dependent electrical resistivity and of thermal expansion were compared. It could be shown that for p- and n-type skutterudites, being hot-pressed and HPT-processed as well as directly HPT-processed from compacted powder, these changes occur more or less simultaneously within the same temperature ranges. This evaluation gives a much deeper insight into the thermoelectric behavior of HPT samples under the influence of changing temperature. 相似文献
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