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11.
Photophysics of a Ruthenium 4H‐Imidazole Panchromatic Dye in Interaction with Titanium Dioxide 下载免费PDF全文
Julian Schindler Dr. Stephan Kupfer Dr. Maria Wächtler Dr. Julien Guthmuller Prof. Dr. Sven Rau Prof. Dr. Benjamin Dietzek 《Chemphyschem》2015,16(5):1061-1070
The photophysics of bis(4,4′‐di‐tert‐butyl‐2,2′‐bipyridine‐κ2N,N′)[2‐(4‐carboxyphenyl)‐4,5‐bis(p‐tolylimino‐κN)imidazolato]ruthenium(II) hexafluorophosphate is investigated, both in solution and attached to a nanocrystalline TiO2 film. The studied substitution pattern of the 4H‐imidazole ligand is observed to block a photoinduced structural reorganization pathway within the 4H‐imidazole ligand that has been previously investigated. Protonation at the 4H‐imidazole ring decreases the excited‐state lifetime in solution. When the unprotonated dye is anchored to TiO2, photoinduced electron injection occurs from thermally nonrelaxed triplet metal‐to‐ligand charge transfer (3MLCT) states with a characteristic time constant of 0.5 ps and an injection efficiency of roughly 25 %. Electron injection from the subsequently populated thermalized 3MLCT state of the dye does not take place. The energy of this state seems to be lower than the conduction band edge of TiO2. 相似文献
12.
This is a survey on recent progress concerning maximal regularity of non-autonomous equations governed by time-dependent forms on a Hilbert space. It also contains two new results showing the limits of the theory. 相似文献
13.
This work is concerned with the development of an efficient two-scale numerical scheme for the prediction of the local and effective mechanical response of heterogeneous materials with non-linear constitutive behavior. In order to ensure both, accurate micromechanical fields and feasible overall CPU-times, an efficient but rather simple solution scheme is proposed. Its capabilities are demonstrated using the FE-FFT method [2,3] for the solution of simple two-scale problems. As an example, two-dimensional polycrystalline microstructures with an elasto-viscoplastic constitutive law are considered. (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
14.
Stephan Trenn 《PAMM》2017,17(1):821-822
Recently, it was suggested in [Shim & Trenn 2015] to use the idea of funnel control in the context of synchronization of multi-agent systems. In that approach each agent is able to measure the difference of its own state and the average state of its neighbours and this synchronization error is used in a typical funnel gain feedback law, see e.g. [Ilchmann & Ryan 2008]. Instead of considering one error signal for each node of the coupling graph (corresponding to an agent) it is also possible to consider one error signal for each edge of the graph. In contrast to the node-wise approach this edgewise funnel synchronization approach results (at least in simulations) in a predictable consensus trajectory. (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
15.
Jan-Niklas Dienemann Shu-Yu Chen Manuel Hitzenberger Montana L. Sievert Stephan M. Hacker Sean T. Prigge Martin Zacharias Michael Groll Stephan A. Sieber 《Angewandte Chemie (International ed. in English)》2023,62(31):e202304533
The development of novel anti-infectives requires unprecedented strategies targeting pathways which are solely present in pathogens but absent in humans. Following this principle, we developed inhibitors of lipoic acid ( LA ) salvage, a crucial pathway for the survival of LA auxotrophic bacteria and parasites but non-essential in human cells. An LA -based probe was selectively transferred onto substrate proteins via lipoate protein ligase (LPL) in intact cells, and their binding sites were determined by mass spectrometry. Probe labeling served as a proxy of LPL activity, enabling in situ screenings for cell-permeable LPL inhibitors. Profiling a focused compound library revealed two substrate analogs ( LAMe and C3 ) as inhibitors, which were further validated by binding studies and co-crystallography. Importantly, LAMe exhibited low toxicity in human cells and achieved killing of Plasmodium falciparum in erythrocytes with an EC50 value of 15 μM, making it the most effective LPL inhibitor reported to date. 相似文献
16.
Henri de Maissin Philipp R. Groß Obaid Mohiuddin Dr. Moritz Weigt Luca Nagel Marvin Herzog Zirun Wang Robert Willing Dr. Wilfried Reichardt Dr. Martin Pichotka Dr. Lisa Heß Prof. Dr. Thomas Reinheckel Prof. Dr. Henning J. Jessen Prof. Dr. Robert Zeiser Prof. Dr. Michael Bock Prof. Dominik von Elverfeldt Prof. Dr. Maxim Zaitsev Dr. Sergey Korchak Dr. Stefan Glöggler Prof. Dr. Jan-Bernd Hövener Prof. Dr. Eduard Y. Chekmenev Prof. Dr. Franz Schilling Dr. Stephan Knecht Dr. Andreas B. Schmidt 《Angewandte Chemie (International ed. in English)》2023,62(36):e202306654
17.
Kinran Lau Felix Niemann Dr. Kaltum Abdiaziz Dr. Markus Heidelmann Yuke Yang Dr. Yujin Tong Dr. Michael Fechtelkord Prof. Torsten C. Schmidt Dr. Alexander Schnegg Prof. R. Kramer Campen Dr. Baoxiang Peng Prof. Martin Muhler Dr. Sven Reichenberger Prof. Stephan Barcikowski 《Angewandte Chemie (International ed. in English)》2023,62(12):e202213968
Both oxygen vacancies and surface hydroxyls play a crucial role in catalysis. Yet, their relationship is not often explored. Herein, we prepare two series of TiO2 (rutile and P25) with increasing oxygen deficiency and Ti3+ concentration by pulsed laser defect engineering in liquid (PUDEL), and selectively quantify the acidic and basic surface OH by fluoride substitution. As indicated by EPR spectroscopy, the laser-generated Ti3+ exist near the surface of rutile, but appear to be deeper in the bulk for P25. Fluoride substitution shows that extra acidic bridging OH are selectively created on rutile, while the surface OH density remains constant for P25. These observations suggest near-surface Ti3+ are highly related to surface bridging OH, presumably the former increasing the electron density of the bridging oxygen to form more of the latter. We anticipate that fluoride substitution will enable better characterization of surface OH and its correlation with defects in metal oxides. 相似文献
18.
Hyehwang Kim Dr. Zheng-wang Qu Prof. Dr. Stefan Grimme Nahil Al-Zuhaika Prof. Dr. Douglas W. Stephan 《Angewandte Chemie (International ed. in English)》2023,62(43):e202312587
The phosphino-phosphonium cations of the form [R3PPR′2]+ are labile and provide access to the constituent Lewis acidic and Lewis basic fragments. This permits frustrated Lewis pair-type addition reactions to alkynes, affording unprecedented phosphino-phosphination reactions and giving cations of the form [cis-R3PCHC(R′′)PR′2]+. This reactivity is further adapted to prepare several examples of a rare class of dissymmetric cis-olefin-linked bidentate phosphines. 相似文献
19.
Felix Unglaube Hanan Atia Stephan Bartling Carsten R. Kreyenschulte Esteban Mejía 《Helvetica chimica acta》2023,106(2):e202200167
The synthesis of primary alcohols (from olefins) is an important and challenging transformation, as most of the current methods suffer from regioselectivity issues. This work describes the utilization of rice husk (RH) from agricultural waste as support for the preparation of a catalyst for the conversion of olefin oxides to primary alcohols. The catalyst was synthesized by pyrolysis of RH impregnated with nickel, and characterized by IR, AAS, XRD, BET, XPS, TEM, and TPD technics. The catalyst shows excellent activity and selectivity towards anti-Markovnikov alcohols, acting simultaneously as Brønsted acid, solid Lewis acid, and as hydrogenation catalyst. A substrate screening was done, the catalyst's recycling stability was assessed, and a plausibly reaction mechanism was proposed. 相似文献
20.
Low water vapor and air permeability is a persistent challenge in wearable and on-skin electronics, as it reduces wearing comfort, and leads to skin irritation and inflammation in the long term. To tackle this issue, Zheng and coworkers designed a stretchable conductor based on an elastomeric fiber mat coated by liquid metal. After simple activation via stretching, the flexible conductor was endowed with excellent permeability, good stretchability, exceptional electrical stability, and good biocompatibility, ascribed to the mesh-like structure and the vertically buckled structure of the liquid metal. Based on the intriguing properties of the material, it was employed in a multi-functional wearable device, able to detect the heartbeat and sweat while serving as a heating device. The corresponding research has been published in Nature Materials and can be accessed at https://doi.org/10.1038/s41563-020-00902-3. 相似文献