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1.
Aulbach Stefan Falk Michael Fuller Timo 《Annals of the Institute of Statistical Mathematics》2019,71(3):599-626
Annals of the Institute of Statistical Mathematics - A multivariate distribution function F is in the max-domain of attraction of an extreme value distribution if and only if this is true for the... 相似文献
2.
Matthias Uhl Tanja Geng Philipp A. Schuster Benjamin W. Schick Matthias Kruck Alexander Fuoss Prof. Dr. Alexander J. C. Kuehne Prof. Dr. Timo Jacob 《Angewandte Chemie (International ed. in English)》2023,62(2):e202214927
For sustainable energy storage, all-organic batteries based on redox-active polymers promise to become an alternative to lithium ion batteries. Yet, polymers contribute to the goal of an all-organic cell as electrodes or as solid electrolytes. Here, we replace the electrolyte with a deep eutectic solvent (DES) composed of sodium bis(trifluoromethanesulfonyl)imide (NaTFSI) and N-methylacetamide (NMA), while using poly(2,2,6,6-tetramethylpiperidin-1-yl-oxyl methacrylate) (PTMA) as cathode. The successful combination of a DES with a polymer electrode is reported here for the first time. The electrochemical stability of PTMA electrodes in the DES at the eutectic molar ratio of 1 : 6 is comparable to conventional battery electrolytes. More viscous electrolytes with higher salt concentration can hinder cycling at high rates. Lower salt concentration leads to decreasing capacities and faster decomposition. The eutectic mixture of 1 : 6 is best suited uniting high stability and moderate viscosity. 相似文献
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4.
Timo Glaser Jannick Meinecke Lukas Freund Dr. Christian Länger Jan-Niclas Luy Prof. Dr. Ralf Tonner Prof. Dr. Ulrich Koert Prof. Dr. Michael Dürr 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(31):8082-8087
The additive-free tetrazine/enol ether click reaction was performed in ultra-high vacuum (UHV) with an enol ether group covalently linked to a silicon surface: Dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate molecules were coupled to the enol ether group of a functionalized cyclooctyne which was adsorbed on the silicon (001) surface via the strained triple bond of cyclooctyne. The reaction was observed at a substrate temperature of 380 K by means of X-ray photoelectron spectroscopy (XPS). A moderate energy barrier was deduced for this click reaction in vacuum by means of density functional theory based calculations, in good agreement with the experimental results. This UHV-compatible click reaction thus opens a new, flexible route for synthesizing covalently bound organic architectures. 相似文献
5.
Johannes Kretsch Anne-Kathrin Kreyenschmidt Timo Schillmöller Dr. Märt Lõkov Dr. Regine Herbst-Irmer Prof. Dr. Ivo Leito Prof. Dr. Dietmar Stalke 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(38):9858-9865
A novel sterically demanding bis(4-benzhydryl-benzoxazol-2-yl)methane ligand 6 (4−BzhH2BoxCH2) was gained in a straightforward six-step synthesis. Starting from this ligand monomeric [M(4-BzhH2BoxCH)] (M=Na ( 7 ), K ( 81 )) and dimeric [{M(4-BzhH2BoxCH)}2] (M=K ( 82 ), Rb ( 9 ), Cs ( 10 )) alkali metal complexes were synthesised by deprotonation. Abstraction of the potassium ion of 8 by reaction with 18-crown-6 resulted in the solvent separated ion pair [{(THF)2K@(18-crown-6)}{bis(4-benzhydryl-benzoxazol-2-yl)methanide}] ( 11 ), including the energetically favoured monoanionic (E,E)-(4-BzhH2BoxCH) ligand. Further reaction of 4−BzhH2BoxCH2 with three equivalents KH and two equivalents 18-crown-6 yielded polymeric [{(THF)2K@(18-crown-6)}{K@(18-crown-6)K(4-BzhBoxCH)}]n (n→∞) ( 12 ) containing a trianionic ligand. The neutral ligand and herein reported alkali complexes were characterised by single X-ray analyses identifying the latter as a promising precursor for low-valent main group complexes. 相似文献
6.
Lukas Martin Müller-Wirtz Daniel Kiefer Sven Ruffing Timo Brausch Tobias Hüppe Daniel I. Sessler Thomas Volk Tobias Fink Sascha Kreuer Felix Maurer 《Molecules (Basel, Switzerland)》2021,26(11)
Exhaled aliphatic aldehydes were proposed as non-invasive biomarkers to detect increased lipid peroxidation in various diseases. As a prelude to clinical application of the multicapillary column–ion mobility spectrometry for the evaluation of aldehyde exhalation, we, therefore: (1) identified the most abundant volatile aliphatic aldehydes originating from in vitro oxidation of various polyunsaturated fatty acids; (2) evaluated emittance of aldehydes from plastic parts of the breathing circuit; (3) conducted a pilot study for in vivo quantification of exhaled aldehydes in mechanically ventilated patients. Pentanal, hexanal, heptanal, and nonanal were quantifiable in the headspace of oxidizing polyunsaturated fatty acids, with pentanal and hexanal predominating. Plastic parts of the breathing circuit emitted hexanal, octanal, nonanal, and decanal, whereby nonanal and decanal were ubiquitous and pentanal or heptanal not being detected. Only pentanal was quantifiable in breath of mechanically ventilated surgical patients with a mean exhaled concentration of 13 ± 5 ppb. An explorative analysis suggested that pentanal exhalation is associated with mechanical power—a measure for the invasiveness of mechanical ventilation. In conclusion, exhaled pentanal is a promising non-invasive biomarker for lipid peroxidation inducing pathologies, and should be evaluated in future clinical studies, particularly for detection of lung injury. 相似文献
7.
Teemu Näykki Timo Sara-Aho Tero Väisänen Ivo Leito 《International journal of environmental analytical chemistry》2015,95(1):1-15
A novel tool for the investigation of stability of total mercury in water samples is presented. The study focuses on the application of enriched 196Hg stable isotopic reagent for the stability studies. Natural abundance of 196Hg in water samples is only 0.15%. Thus, the use of the 196Hg isotope spike represents a major advantage, when it can be assumed that all the measured isotope is the same as is accurately added by the analyst, and the change in its mass concentration can be followed simply and reliably. Tests were carried out with industrial waste water and two type of the natural water. Cold vapour (CV) inductively coupled plasma mass spectrometer (ICP-MS) technique was applied for the mercury measurements. Monitoring was continued for approximately 100 days. It is commonly advised that the measurement for total mercury in water samples should be carried out within 14 days. In this study the samples were observed to be stable for more than three months, if they were stored at a temperature of 4–6°C. The results of this stability study were in line with the guidance presented in EPA standard 1631. However, the samples were noticed to be stable for a much longer time than is presented in the standard method ISO 17852. 相似文献
8.
Steffen Styra Dr. Mohand Melaimi Dr. Curtis E. Moore Prof. Arnold. L. Rheingold Timo Augenstein Prof. Dr. Frank Breher Prof. Guy Bertrand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(23):8441-8446
A stable cyclic (alkyl)(amino)carbene (CAAC) 1 inserts into the para‐CF bond of pentafluoropyridine, and after fluoride abstraction, the iminium‐pyridyl adduct [ 3 ]+ was isolated. A cyclic voltammetry study shows a reversible three‐state redox system involving [ 3 ]+, [ 3 ] ? , and [ 3 ] ? . The CAAC‐pyridyl radical [ 3 ] ? , obtained by reduction of [ 3 ]+ with magnesium, has been spectroscopically and crystallographically characterized. In contrast to the lack of π communication between the CAAC and the pyridine units in cation [ 3 ]+, the unpaired electron of [ 3 ] ? is delocalized over an extended π system involving both heterocycles. 相似文献
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10.
Back Cover: Intramolecular Frustrated Lewis Pair with the Smallest Boryl Site: Reversible H2 Addition and Kinetic Analysis (Angew. Chem. Int. Ed. 6/2015) 下载免费PDF全文