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31.
Adrian Adamski Andrzej Biadasz Krzysztof Domieracki Marek Andrzej Kojdecki Dominik Paukszta Dominika Uryzaj 《Liquid crystals》2013,40(4):456-462
Liquid-crystalline perylene-3,4,9,10-tetra-(n-hexylester) forms characteristic dendritic or flower-like structures at room temperature when it is deposited on a hydrophilic glass substrate using the zone-casting technique. It was found that such unique structures were not possible to be created simply by recrystallisation of this dye from a liquid-crystalline columnar phase. On the basis of the observations using a confocal microscope and the study of wide angle X-ray scattering (WAXS) as well as the analysis of the absorption and fluorescence spectra, some conclusions, concerning the molecular organisation in the dendritic structure, are drawn. Based on the research, one can assume that the dendrites are formed by columnar molecular aggregates with the column axes parallel to the substrate. Such an organisation of the molecules can be interesting from the point of view of organic electronics. 相似文献
32.
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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Peter Fechner Oliver Bleher Melanie Ewald Kathrin Freudenberger Dominik Furin Urs Hilbig Felix Kolarov Katrin Krieg Lothar Leidner Goran Markovic Günther Proll Florian Pröll Sabrina Rau Johannes Riedt Barbara Schwarz Patricia Weber Julia Widmaier 《Analytical and bioanalytical chemistry》2014,406(17):4033-4051
This review is focused on methods for detecting small molecules and, in particular, the characterisation of their interaction with natural proteins (e.g. receptors, ion channels). Because there are intrinsic advantages to using label-free methods over labelled methods (e.g. fluorescence, radioactivity), this review only covers label-free techniques. We briefly discuss available techniques and their advantages and disadvantages, especially as related to investigating the interaction between small molecules and proteins. The reviewed techniques include well-known and widely used standard analytical methods (e.g. HPLC-MS, NMR, calorimetry, and X-ray diffraction), newer and more specialised analytical methods (e.g. biosensors), biological systems (e.g. cell lines and animal models), and in-silico approaches. 相似文献
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We propose to solve time-periodic Navier–Stokes problems by a discrete Fourier transform in time. Truncating the Fourier series yields a nonlinear system of equations for the unknown Fourier coefficients. Its solution by Picard iteration requires to solve a sequence of linear systems of equations. The focus of this work is on an efficient method to solve these linear systems. We employ GMRES, complemented by an optimal block triangular preconditioner. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
37.
This review gives a current opinion on the state of the art of ion rectifying solid-state nanopore sensors, as well as on the recent directions and challenges of the field, focusing in particular on the progress made in the last two to three years. The review explains the phenomenon of ion current rectification in geometrically asymmetric nanopores and the principle of sensing with these systems. Aside from the conventional approach of analyte immobilization onto the pore surface, some intriguing sensing schemes that decouple the pore selectivity from the surface and promise a more flexible sensing approach are also presented. Lastly, an overview of the recent effort towards amplifying the ion currents and the rectification of these sensors is given, followed by a brief discussion of future perspectives for the field. 相似文献
38.
Ntombizethu Nokuphiwa Msomi Tiara Padayachee Nomfundo Nzuza Puleng Rosinah Syed Justyna Dorota Kry Wanping Chen Dominik Gront David R. Nelson Khajamohiddin Syed 《Molecules (Basel, Switzerland)》2021,26(6)
The impact of lifestyle on shaping the genome content of an organism is a well-known phenomenon and cytochrome P450 enzymes (CYPs/P450s), heme-thiolate proteins that are ubiquitously present in organisms, are no exception. Recent studies focusing on a few bacterial species such as Streptomyces, Mycobacterium, Cyanobacteria and Firmicutes revealed that the impact of lifestyle affected the P450 repertoire in these species. However, this phenomenon needs to be understood in other bacterial species. We therefore performed genome data mining, annotation, phylogenetic analysis of P450s and their role in secondary metabolism in the bacterial class Gammaproteobacteria. Genome-wide data mining for P450s in 1261 Gammaproteobacterial species belonging to 161 genera revealed that only 169 species belonging to 41 genera have P450s. A total of 277 P450s found in 169 species grouped into 84 P450 families and 105 P450 subfamilies, where 38 new P450 families were found. Only 18% of P450s were found to be involved in secondary metabolism in Gammaproteobacterial species, as observed in Firmicutes as well. The pathogenic or commensal lifestyle of Gammaproteobacterial species influences them to such an extent that they have the lowest number of P450s compared to other bacterial species, indicating the impact of lifestyle on shaping the P450 repertoire. This study is the first report on comprehensive analysis of P450s in Gammaproteobacteria. 相似文献
39.
Dominik Raiser Dr. Hartmut Schubert Prof. Dr. Holger F. Bettinger Prof. Dr. Lars Wesemann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(6):1981-1983
Halide and phenyl substituted germaborenes were shown to react with azides at room temperature and transfer a borylene moiety to give iminoboranes. This iminoborane synthesis based on a borylene transfer route was investigated computationally in the case of the phenyl substituted germaborene. 相似文献
40.
Dr. Dominik Raiser Dr. Klaus Eichele Dr. Hartmut Schubert Prof. Dr. Lars Wesemann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(56):14073-14080
The reaction of the intramolecular germylene-phosphine Lewis pair (o-PPh2)C6H4GeAr* ( 1 ) with Group 15 element trichlorides ECl3 (E=P, As, Sb) was investigated. After oxidative addition, the resulting compounds (o-PPh2)C6H4(Ar*)Ge(Cl)ECl2 ( 2 : E=P, 3 : E=As, 4 : E=Sb) were reduced by using sodium metal or LiHBEt3. The molecular structures of the phosphine-stabilized phosphinidene (o-PPh2)C6H4(Ar*)Ge(Cl)P ( 5 ), arsinidene (o-PPh2)C6H4(Ar*)Ge(Cl)As ( 6 ) and stibinidene (o-PPh2)C6H4(Ar*)Ge(Cl)Sb ( 7 ) are presented; they feature a two-coordinate low-valent Group 15 element. After chloride abstraction, a cyclic germaphosphene [(o-PPh2)C6H4(Ar*)GeP] [B(C6H3(CF3)2)4] ( 8 ) was isolated. The 31P NMR data of the germaphosphene were compared with literature examples and analyzed by quantum chemical calculations. The phosphinidene was treated with [iBu2AlH]2, and the product of an Al−H addition to the low-valent phosphorus atom (o-PPh2)C6H4(Ar*)Ge(H)P(H)Al(C4H9)2 ( 9 ) was characterized. 相似文献