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Joachim Heine Gerd-Volker Röschenthaler 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4)
Abstract The dimer of hexafluorothioacetone reacted with various phosphites to form thiophosphates and bis(trifluoromethyl)methylenphosphoranes, being unstable in the case of (Me3SiO) P(OMe)3-n, (n=1?3), where phosphonates (Me3SiO)n-1(MeO)3-nP(O)[C(CF3)=CF2] (n=1-3) and Me3SiF were observed. In general, cyclic phosphites behaved similar to acyclic ones. The resulting bis(trifluoromethyl)methylenphosphoranes were thermally stable except compound A, because of a new intramolecular fluorine transfer to phosphorus forming fluorophosphorane B. 相似文献
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Olaf Böge Eckhart Nietzschmann Joachim Heinicke 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):25-29
Abstract 2-Bromoaryloxy-chloromethyldiorganosilanes react with sodium in a one-pot-reaction via metallation, [1,3]-carbanionic rearrangement and cyclization to give diorgano-1,3-benzoxasilolenes. The title compounds have been characterized by n.m.r. spectroscopic data and an alternative independent synthesis. 相似文献
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How preparation and modification parameters affect PB‐PEO polymersome properties in aqueous solution 下载免费PDF全文
Joachim Habel Anayo Ogbonna Nanna Larsen Simon Krabbe Kristoffer Almdal Claus Hélix‐Nielsen 《Journal of Polymer Science.Polymer Physics》2016,54(16):1581-1592
The effect of formation and modification methods on the physical properties of polymersomes is critical for their use in applications relying on their ability to mimic functional properties of biological membranes. In this study, we compared two formation methods for polymersomes made from polybutadiene‐polyethylene oxide diblock copolymers: detergent‐mediated film rehydration (DFR) and solvent evaporation (SE). DFR‐prepared polymersomes showed a three times higher permeability compared to SE‐prepared polymersomes as revealed by stopped‐flow light scattering. SE‐prepared polymersomes broke down faster to structures <50 nm diameter when processed with extrusion, which was more pronounced at 5 mg mL?1, compared to 10, 20, and 25 mg mL?1. Our results indicate that the bilayer of SE‐prepared polymersomes has a lower apparent fluidity. We also investigated the role of n‐octyl‐β‐d ‐glucopyranoside (OG), a detergent typically used for reconstitution of membrane proteins into lipid bilayers. Specifically, we compared dialysis and biobeads for OG removal to investigate the influence of these methods on bilayer conformation and polymer rearrangement following detergent removal. There was no significant difference found between method, temperature, or time within each method. Our findings provide insight on how biocompatible polymersome production affects the physical properties of the resulting polymersomes. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1581–1592 相似文献
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Reassessment of the NH4NO3 thermal decomposition technique for calibration of the N2O isotopic composition 下载免费PDF全文
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