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991.
992.
Felix Brosge Thomas Lorenz Priv.-Doz. Dr. Holger Helten Prof. Dr. Carsten Bolm 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(55):12708-12711
While polysulfones constitute a class of well-established, highly valuable applied materials, knowledge about polymers based on the related sulfoximine group is very limited. We have employed functionalized diaryl sulfoximines and a p-phenylene bisborane as building blocks for unprecedented BN- and BO-doped alternating inorganic–organic hybrid copolymers. While the former were accessed by a facile silicon/boron exchange protocol, the synthesis of polymers with main-chain B–O linkages was achieved by salt elimination. 相似文献
993.
Pd@Pt Core–Shell Nanoparticles with Branched Dandelion‐like Morphology as Highly Efficient Catalysts for Olefin Reduction 下载免费PDF全文
Kasibhatta Josena Datta Dr. Kasibhatta Kumara Ramanatha Datta Dr. Manoj B. Gawande Dr. Vaclav Ranc Dr. Klára Čépe Dr. Victor Malgras Prof. Yusuke Yamauchi Prof. Rajender S. Varma Prof. Dr. Radek Zboril 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(5):1577-1581
A facile synthesis based on the addition of ascorbic acid to a mixture of Na2PdCl4, K2PtCl6, and Pluronic P123 results in highly branched core–shell nanoparticles (NPs) with a micro–mesoporous dandelion‐like morphology comprising Pd core and Pt shell. The slow reduction kinetics associated with the use of ascorbic acid as a weak reductant and suitable Pd/Pt atomic ratio (1:1) play a principal role in the formation mechanism of such branched Pd@Pt core–shell NPs, which differs from the traditional seed‐mediated growth. The catalyst efficiently achieves the reduction of a variety of olefins in good to excellent yields. Importantly, higher catalytic efficiency of dandelion‐like Pd@Pt core–shell NPs was observed for the olefin reduction than commercially available Pt black, Pd NPs, and physically admixed Pt black and Pd NPs. This superior catalytic behavior is not only due to larger surface area and synergistic effects but also to the unique micro–mesoporous structure with significant contribution of mesopores with sizes of several tens of nanometers. 相似文献
994.
995.
996.
997.
Orthogonal Click Conjugation to the Liposomal Surface Reveals the Stability of the Lipid Anchorage as Crucial for Targeting 下载免费PDF全文
Thomas Fritz Matthias Voigt Matthias Worm Inka Negwer Dr. Sophie S. Müller Kathrin Kettenbach Prof. Tobias L. Ross Prof. Frank Roesch Dr. Kaloian Koynov Prof. Holger Frey Prof. Mark Helm 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(33):11578-11582
Synthetic access to multiple surface decorations are a bottleneck in the development of liposomes for receptor mediated targeting. This opens a complex multiparameter space, exploration of which is severely limited in terms of sample numbers and turnaround times. Here, we unlock this technological barrier by a combination of a milligram‐scale liposome formulation using dual centrifugation and orthogonal click chemistry on the liposomal surface. Application of these techniques to conceptually new amphiphilic compounds, which feature norbornene and alkyne groups at the apex of sterically stabilizing, hyperbranched polyglycerol moieties, revealed a particular influence of the membrane anchor of functional amphiphiles. Folic acid residues clicked to cholesterol‐based amphiphiles were inefficient in folate‐mediated cell targeting, while dialkyl‐anchored amphiphiles remained stable in the liposomal membrane and imparted efficient targeting properties. These findings are of specific importance considering the popularity of cholesterol as a lipophilic anchor. 相似文献
998.
999.
Volker Pohl Fanny Yang Holger Boche 《Journal of Fourier Analysis and Applications》2014,20(6):1212-1233
This paper considers the recovery of continuous signals in infinite dimensional spaces from the magnitude of their frequency samples. It proposes a sampling scheme which involves a combination of oversampling and modulations with complex exponentials. Sufficient conditions are given such that almost every signal with compact support can be reconstructed up to a unimodular constant using only its magnitude samples in the frequency domain. Finally it is shown that an average sampling rate of four times the Nyquist rate is enough to reconstruct almost every time-limited signal. 相似文献
1000.
We describe the characteristics of a radially spreading unstable liquid sheet in quiescent air via optical measurement techniques
and linear instability theory. A high speed CCD camera system and a complimentary laser refraction method were employed to
measure the intact sheet diameter, unstable wave lengths, wave speed, wave frequency spectrum and spatial wave growth rates.
Linear instability models for thinning, viscous and inviscid liquid sheets, which are available from the literature, allow
for a comparison of experimental data and predicted sheet behaviour. The last section evaluates the differences and similarities
between the current liquid sheet experiment and industrial spray applications such as fuel atomisation via pressure-swirl
nozzles. 相似文献