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111.
Moritz Emanuel?BeberEmail author Dieter?Armbruster Marc-Thorsten?Hütt 《The European Physical Journal B - Condensed Matter and Complex Systems》2013,86(11):473
Modules are common functional and structural properties of many social, technical andbiological networks. Especially for biological systems it is important to understand howmodularity is related to function and how modularity evolves. It is known thattime-varying or spatially organized goals can lead to modularity in a simulated evolutionof signaling networks. Here, we study a minimal model of material flow in networks. Wediscuss the relation between the shared use of nodes, i.e., the cooperativity of modules,and the orthogonality of a prescribed output pattern. We study the persistence ofcooperativity through an evolution of robustness against local damages. We expect theresults to be valid for a large class of flow-based biological and technical networks. 相似文献
112.
113.
Elizabeth Galati Huachen Tao Moritz Tebbe Rija Ansari Michael Rubinstein Ekaterina B. Zhulina Eugenia Kumacheva 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(10):3155-3159
Chiral packing of ligands on the surface of nanoparticles (NPs) is of fundamental and practical importance, as it determines how NPs interact with each other and with the molecular world. Herein, for gold nanorods (NRs) capped with end‐grafted nonchiral polymer ligands, we show a new mechanism of chiral surface patterning. Under poor solvency conditions, a smooth polymer layer segregates into helicoidally organized surface‐pinned micelles (patches). The helicoidal morphology is dictated by the polymer grafting density and the ratio of the polymer ligand length to nanorod radius. Outside this specific parameter space, a range of polymer surface structures was observed, including random, shish‐kebab, and hybrid patches, as well as a smooth polymer layer. We characterize polymer surface morphology by theoretical and experimental state diagrams. The helicoidally organized polymer patches on the NR surface can be used as a template for the helicoidal organization of other NPs, masked synthesis on the NR surface, as well as the exploration of new NP self‐assembly modes. 相似文献
114.
Andrei Hutanu Steffen Kiessig Andrea Bathke Rolf Ketterer Sonja Riner Jan Olaf Stracke Markus Wild Bernd Moritz 《Electrophoresis》2019,40(22):3014-3022
Charge heterogeneity profiling is important for the quality control (QC) of biopharmaceuticals. Because of the increasing complexity of these therapeutic entities [1], the development of alternative analytical techniques is needed. In this work, flow‐through partial‐filling affinity capillary electrophoresis (FTPFACE) has been established as a method for the analysis of a mixture of two similar monoclonal antibodies (mAbs). The addition of a specific ligand results in the complexation of one mAb in the co‐formulation, thus changing its migration time in the electric field. This allows the characterization of the charged variants of the non‐shifted mAb without interferences. Adsorption of proteins to the inner capillary wall has been circumvented by rinsing with guanidine hydrochloride before each injection. The presented FTPFACE approach requires only very small amounts of ligands and provides complete comparability with a standard CZE of a single mAb. 相似文献
115.
Moritz Balkenhohl Harish Jangra Tobias Lenz Marian Ebeling Hendrik Zipse Konstantin Karaghiosoff Paul Knochel 《Angewandte Chemie (International ed. in English)》2019,58(27):9244-9247
Mono‐ or bidentate boron Lewis acids trigger a regioselective magnesiation or zincation of pyridazine in position C3 (ortho product) or C4 (meta product). The regioselectivity of the metalation was rationalized with the help of calculated pKa values of both pyridazine and pyridazine/Lewis acid complexes. 相似文献
116.
Preparation of Polyfunctional Arylzinc Organometallics in Toluene by Halogen/Zinc Exchange Reactions
Moritz Balkenhohl Dorothe S. Ziegler Alexandre Desaintjean Leonie J. Bole Alan R. Kennedy Eva Hevia Paul Knochel 《Angewandte Chemie (International ed. in English)》2019,58(37):12898-12902
A wide range of polyfunctional diaryl‐ and diheteroarylzinc species were prepared in toluene within 10 min to 5 h through an I/Zn or Br/Zn exchange reaction using bimetallic reagents of the general formula R′2Zn?2 LiOR (R′=sBu, tBu, pTol). Highly sensitive functional groups, such as a triazine, a ketone, an aldehyde, or a nitro group, were tolerated in these exchange reactions, enabling the synthesis of a plethora of functionalized (hetero)arenes after quenching with various electrophiles. Insight into the constitution and reactivity of these bimetallic mixtures revealed the formation of highly active lithium diorganodialkoxyzincates of type [R′2Zn(OR)2Li2]. 相似文献
117.
We have experimentally demonstrated how two beams of light separated by an octave in frequency can become entangled after their interaction in a chi;{(2)} nonlinear medium. The entangler was a nonlinear optical resonator that was strongly driven by coherent light at the fundamental and second-harmonic wavelengths. An interconversion between the fields created quantum correlations in the amplitude and phase quadratures, which were measured by two independent homodyne detectors. Analysis of the resulting correlation matrix revealed a wave function inseparability of 0.74(1)<1, thereby satisfying the criterion of entanglement. 相似文献
118.
We demonstrate a passively mode-locked femtosecond Yb:KLu(WO(4))(2) thin-disk laser oscillator. Chirped-pulse operation in the positive dispersion regime as well as solitary operation have been realized, and the laser performance of both configurations are compared. In the solitary mode-locking regime the output power exceeds 25 W in a diffraction-limited beam, and pulse durations as short as 440 fs at a 34.7 MHz repetition rate have been generated. For the first time we present a chirped-pulse operation of a thin-disk oscillator that yields a maximum average output power of 9.5 W with a Fourier limit of 450 fs. 相似文献
119.
Dr. Moritz Balkenhohl Prof. Dr. Paul Knochel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(17):3688-3697
For the preparation of zinc organometallics bearing highly sensitive functional groups such as ketones, aldehydes or nitro groups, especially mild halogen–zinc exchange reagents have proven to be of great potential. In this Minireview, the latest research in the area of the halogen–zinc exchange reaction is reported, with a special focus lying on novel dialkylzinc reagents complexed with lithium alkoxides. Additionally, the preparation and application of organofluorine zinc reagents and transition-metal-catalyzed halogen–zinc exchange reactions are reviewed. 相似文献
120.