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991.
Dr. Ran Du Dr. Jan-Ole Joswig Dr. René Hübner Lin Zhou Dr. Wei Wei Prof. Yue Hu Prof. Dr. Alexander Eychmüller 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(21):8370-8377
Noble-metal aerogels (NMAs) have drawn increasing attention because of their self-supported conductive networks, high surface areas, and numerous optically/catalytically active sites, enabling their impressive performance in diverse fields. However, the fabrication methods suffer from tedious procedures, long preparation times, unavoidable impurities, and uncontrolled multiscale structures, discouraging their developments. By utilizing the self-healing properties of noble-metal aggregates, the freezing-promoted salting-out behavior, and the ice-templating effect, a freeze–thaw method is crafted that is capable of preparing various hierarchically structured noble-metal gels within one day without extra additives. In light of their cleanliness, the multi-scale structures, and combined catalytic/optical properties, the electrocatalytic and photoelectrocatalytic performance of NMAs are demonstrated, which surpasses that of commercial noble-metal catalysts. 相似文献
992.
993.
994.
995.
Cihang Yu Dr. Agnes Kütt Prof. Dr. Gerd-Volker Röschenthaler Dr. Tomas Lebl Dr. David B. Cordes Prof. Dr. Alexandra M. Z. Slawin Prof. Dr. Michael Bühl Prof. Dr. David O'Hagan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(45):20077-20081
We report the synthesis of all-cis 1,2,4,5-tetrakis (trifluoromethyl)- and all-cis 1,2,3,4,5,6-hexakis (trifluoromethyl)- cyclohexanes by direct hydrogenation of precursor tetrakis- or hexakis- (trifluoromethyl)benzenes. The resultant cyclohexanes have a stereochemistry such that all the CF3 groups are on the same face of the cyclohexyl ring. All-cis 1,2,3,4,5,6-hexakis(trifluoromethyl)cyclohexane is the most sterically demanding of the all-cis hexakis substituted cyclohexanes prepared to date, with a barrier (ΔG) to ring inversion calculated at 27 kcal mol−1. The X-ray structure of all-cis 1,2,3,4,5,6-hexakis(trifluoromethyl)cyclohexane displays a flattened chair conformation and the electrostatic profile of this compound reveals a large diffuse negative density on the fluorine face and a focused positive density on the hydrogen face. The electropositive hydrogen face can co-ordinate chloride (K≈103) and to a lesser extent fluoride and iodide ions. Dehydrofluorination promoted decomposition occurs with fluoride ion acting as a base. 相似文献
996.
997.
Dr. Rainer Müller Dr. Mevlut Citir Dr. Sebastian Hauke Prof. Dr. Carsten Schultz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(2):384-389
Phosphatidylinositol (PI) is the biosynthetic precursor for seven phosphoinositides, important signaling lipids in cells. A membrane-permeant caged PI derivative featuring a photo-removable coumarinyl group masking the negative charge of the phosphate, as well as two enzymatically removable butyrate esters for increased lipophilicity and for preventing phosphate migration, were synthesized. Rapid cell entry and cellular labeling in fixed cells was demonstrated by a photo-cross-linkable diazirine followed by attachment of a fluorophore through click chemistry. Using this technique, we found that the multifunctional caged PI derivative resided predominantly at internal membranes but rapidly changed to the plasma membrane after uncaging. Accordingly, a preliminary proteomic analysis of the lipid–protein conjugates revealed that the two major PI transport proteins PITPα and β were prime targets of the photo-cross-linked PI derivative. 相似文献
998.
Canbay Canan Aksu Aziz Baiz Sivar Özkul İskender Dere Aysegül 《Journal of Thermal Analysis and Calorimetry》2020,139(2):831-831
Journal of Thermal Analysis and Calorimetry - In the original publication of the article, the second author’s family name was incorrectly published. 相似文献
999.
Gafour M. H. Saïl K. Bassou G. Haouzi A. Maloufi N. 《Journal of Experimental and Theoretical Physics》2020,131(4):548-557
Journal of Experimental and Theoretical Physics - Density functional calculations in periodic boundary conditions (PBCs) were performed to investigate the structural and electronic properties of... 相似文献
1000.
The Ramanujan Journal - In this paper we evaluate quadratic sums of Gaussian q-binomial coefficients with two additional parameters. We obtain a general summation theorem using a combination of... 相似文献