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981.
Paul Schmid Dr. Felipe Fantuzzi Jonas Klopf Niklas B. Schröder Dr. Rian D. Dewhurst Prof. Holger Braunschweig Prof. Volker Engel Prof. Bernd Engels 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(16):5051-5051
Invited for the cover of this issue is Bernd Engels, Holger Braunschweig, Volker Engel and their coworkers at University of Würzburg. The image depicts bridged boron compounds which possess fascinating relationships between their composition and their geometrical and electronic structures, the latter ranging from closed-shell to biradical triplet or singlet ground state. Read the full text of the article at 10.1002/chem.202004619 . 相似文献
982.
Isaac Choi Zhigao Shen Dr. Emanuel Ronge Dr. Volker Karius Prof. Dr. Christian Jooss Prof. Dr. Lutz Ackermann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(50):12737-12741
Herein, we disclose a recyclable, hybrid manganese catalyst for site-selective azine C−H activation by weak amide assistance. The novel, reusable catalyst enabled C3–H arylation and C3–H alkylation with ample scope, and was characterized by detailed transmission electron microscopy analysis. 相似文献
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Glycoluril‐Derived Molecular Clips are Potent and Selective Receptors for Cationic Dyes in Water 下载免费PDF全文
Prof. Dr. Nengfang She Dr. Damien Moncelet Dr. Laura Gilberg Dr. Xiaoyong Lu Prof. Dr. Vladimir Sindelar Prof. Dr. Volker Briken Prof. Dr. Lyle Isaacs 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(43):15270-15279
Molecular clip 1 remains monomeric in water and engages in host–guest recognition processes with suitable guests. We report the Ka values for 32 1? guest complexes measured by 1H NMR, UV/Vis, and fluorescence titrations. The cavity of 1 is shaped by aromatic surfaces of negative electrostatic potential and therefore displays high affinity and selectivity for planar and cationic aromatic guests that distinguishes it from CB[n] receptors that prefer aliphatic over aromatic guests. Electrostatic effects play a dominant role in the recognition process whereby ion–dipole interactions may occur between ammonium ions and the C=O groups of 1 , between the SO3? groups of 1 and pendant cationic groups on the guest, and within the cavity of 1 by cation–π interactions. Host 1 displays a high affinity toward dicationic guests with large planar aromatic surfaces (e.g. naphthalene diimide NDI+ and perylene diimide PDI+) and cationic dyes derived from acridine (e.g. methylene blue and azure A). The critical importance of cation–π interactions was ascertained by a comparison of analogous neutral and cationic guests (e.g. methylene violet vs. methylene blue; quinoline vs. N‐methylquinolinium; acridine vs. N‐methylacridinium; neutral red vs. neutral red H+) the affinities of which differ by up to 380‐fold. We demonstrate that the high affinity of 1 toward methylene blue (Ka=3.92×107 m ?1; Kd=25 nm ) allows for the selective sequestration and destaining of U87 cells stained with methylene blue. 相似文献
986.
A New Method for Quantitative Marking of Deposited Lithium by Chemical Treatment on Graphite Anodes in Lithium‐Ion Cells 下载免费PDF全文
Yvonne Krämer Claudia Birkenmaier Julian Feinauer Dr. Dr. Andreas Hintennach Conrad L. Bender Dr. Markus Meiler Prof. Dr. Volker Schmidt Prof. Dr. Robert E. Dinnebier Prof. Dr. Thomas Schleid 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(16):6062-6065
A novel approach for the marking of deposited lithium on graphite anodes from large automotive lithium‐ion cells (≥6 Ah) is presented. Graphite anode samples were extracted from two different formats (cylindrical and pouch cells) of pristine and differently aged lithium‐ion cells. The samples present a variety of anodes with various states of lithium deposition (also known as plating). A chemical modification was performed to metallic lithium deposited on the anode surface due to previous plating with isopropanol (IPA). After this procedure an oxygenated species was detected by scanning electron microscopy (SEM), which later was confirmed as Li2CO3 by Fourier transform infrared spectroscopy (FTIR) and X‐ray powder diffraction (XRPD). A valuation of the covered area by Li2CO3 was carried out with an image analysis using energy‐dispersive X‐ray spectroscopy (EDX) and quantitative Rietveld refinement. 相似文献
987.
Back Cover: Divergent Coordination Chemistry: Parallel Synthesis of [2×2] Iron(II) Grid‐Complex Tauto‐Conformers (Angew. Chem. Int. Ed. 36/2016) 下载免费PDF全文
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Hans-Dietrich O. F. Gronau Martin Grüttmüller Sven Hartmann Uwe Leck Volker Leck 《Designs, Codes and Cryptography》2002,27(1-2):49-91
An orthogonal double cover (ODC) is a collection of n spanning subgraphs(pages) of the complete graph K
n such that they cover every edge of the completegraph twice and the intersection of any two of them contains exactly one edge. If all the pages are isomorphic tosome graph G, we speak of an ODC by G. ODCs have been studied for almost 25 years, and existenceresults have been derived for many graph classes. We present an overview of the current state of research alongwith some new results and generalizations. As will be obvious, progress made in the last 10 years is in many waysrelated to the work of Ron Mullin. So it is natural and with pleasure that we dedicate this article to Ron, on theoccasion of his 65th birthday. 相似文献
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