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991.
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Dr. Alexander Scholte Christoph Hübner Dr. Dieter Ströhl Olaf Scheufler Dr. Steffen Czich Julia M. Börke Dr. Gerhard Hildebrand Prof. Dr. Klaus Liefeith 《ChemistryOpen》2021,10(9):889-895
Due to their special chemical structure, tetraether lipids (TEL) represent essential elements of archaeal membranes, providing these organisms with extraordinary properties. Here we describe the characterization of a newly isolated structural element of the main lipids. The TEL fragment GDNT-β-Glu was isolated from Sulfolobus metallicus and characterized in terms of its chemical structure by NMR- and MS-investigations. The obtained data are dissimilar to analogically derived established structures – in essence, the binding relationships in the polar head group are re-determined and verified. With this work, we provide an important contribution to the structure elucidation of intact TEL also contained in other Sulfolobus strains such as Solfulobus acidocaldarius and Sulfolobus solfataricus. 相似文献
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Christoph Loenarz 《Angewandte Chemie (International ed. in English)》2020,59(10):3776-3780
The 2019 Nobel Prize in Physiology or Medicine honours three scientists that devoted their careers to pursuing an audacious basic science question: by what mechanisms do animals sense oxygen, and how can cells adapt to a lack of oxygen? The identification of the human hypoxia inducible factor pathway has enabled new approaches for the therapy of related diseases including cancer, cardiovascular disease, anaemia, and stroke. The intricate molecular details of oxygen sensing broadened interest in the family of iron‐ and 2‐oxoglutarate‐dependent oxygenases known from elaborate natural product chemistry, and catalysed major progress in macromolecule hydroxylation. The laureates’ work enables numerous avenues for molecular scientists, from C?H activation chemistry to PROTAC technology, medicinal chemistry, and epigenetics. 相似文献
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Lisa A. Bischoff Dr. Michael Drisch Dr. Christoph Kerpen Philipp T. Hennig Dr. Johannes Landmann Dr. Jan A. P. Sprenger Dr. Rüdiger Bertermann Dr. Matthias Grüne Qinqin Yuan Dr. Jonas Warneke Dr. Xue-Bin Wang Dr. Nikolai V. Ignat'ev Prof. Dr. Maik Finze 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(14):3560-3574
High-yield syntheses up to molar scales for salts of [BH(CN)3]− ( 2 ) and [BH2(CN)2]− ( 3 ) starting from commercially available Na[BH4] (Na 5 ), Na[BH3(CN)] (Na 4 ), BCl3, (CH3)3SiCN, and KCN were developed. Direct conversion of Na 5 into K 2 was accomplished with (CH3)3SiCN and (CH3)3SiCl as a catalyst in an autoclave. Alternatively, Na 5 is converted into Na[BH{OC(O)R}3] (R=alkyl) that is more reactive towards (CH3)3SiCN and thus provides an easy access to salts of 2 . Some reaction intermediates were identified, for example, Na[BH(CN){OC(O)Et}2] (Na 7 b ) and Na[BH(CN)2{OC(O)Et}] (Na 8 b ). A third entry to 2 and 3 uses ether adducts of BHCl2 or BH2Cl such as the commercial 1,4-dioxane adducts that react with KCN and (CH3)3SiCN. Alkali metal salts of 2 and 3 are convenient starting materials for organic salts, especially for low viscosity ionic liquids (ILs). [EMIm] 3 has the lowest viscosity and highest conductivity with 10.2 mPa s and 32.6 mS cm−1 at 20 °C known for non-protic ILs. The ILs are thermally, chemically, and electrochemically robust. These properties are crucial for applications in electrochemical devices, for example, dye-sensitized solar cells (Grätzel cells). 相似文献
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Yan-Xiang Zhang Dr. Si-Ming Wu Dr. Ge Tian Xiao-Fang Zhao Dr. Li-Ying Wang Dr. Yi-Xia Yin Lu Wu Qian-Ni Li Prof. Dr. Yue-Xing Zhang Prof. Dr. Jin-Song Wu Prof. Dr. Christoph Janiak Prof. Dr. Kenneth I. Ozoemena Prof. Dr. Menny Shalom Prof. Dr. Xiao-Yu Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(57):14202-14208
Photodriven seawater splitting is considered to be one of the most promising techniques for sustainable hydrogen production. However, the high salinity of seawater would deactivate catalysts and consume the photogenerated carriers. Metal vacancies in metal oxide semiconductors are critical to directed electron transfer and high salinity resistance; they are thus desirable but remain a challenge. We demonstrate a facile controllable calcination approach to synthesize TiO2 nanofibers with rich Ti vacancies with excellent photo/electro performances and long-time stability in photodriven seawater splitting, including photocatalysis and photo-electrocatalysis. Experimental measurements and theoretical calculations reveal the formation of titanium vacancies, as well as unidirectional electron trap and superior H+ adsorption ability for efficient charge transfer and resistance to corrosion by seawater. Therefore, atomic-/nanoscale characteristics and mechanism have been proposed to clarify the generation of titanium vacancies and the corresponding interfacial electron transfer. 相似文献
1000.
Bestehorn Felix Hansknecht Christoph Kirches Christian Manns Paul 《Mathematical Programming》2021,188(2):621-652
Mathematical Programming - We investigate an extension of Mixed-Integer Optimal Control Problems by adding switching costs, which enables the penalization of chattering and extends current modeling... 相似文献