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71.
Hagihara S Gremaud L Bollot G Mareda J Matile S 《Journal of the American Chemical Society》2008,130(13):4347-4351
Synthetic ion channels and pores attract current attention as multicomponent sensors in complex matrixes. This application requires the availability of reactive signal amplifiers that covalently capture analytes and drag them into the pore. pi-Basic 1,5-dialkoxynaphthalenes (1,5-DAN) are attractive amplifiers because aromatic electron donor-acceptor (AEDA) interactions account for their recognition within pi-acidic naphthalenediimide (NDI) rich synthetic pores. Focusing on amplifier design, we report here the synthesis of a complete collection of DAN and dialkoxyanthracene amplifiers, determine their oxidation potentials by cyclic voltammetry, and calculate their quadrupole moments. Blockage experiments reveal that subtle structural changes in regioisomeric DAN amplifiers can be registered within NDI pores. Frontier orbital overlap in AEDA complexes, oxidation potentials, and, to a lesser extent, quadrupole moments are shown to contribute to isomer recognition by synthetic pores. Particularly important with regard to practical applications of synthetic pores as multianalyte sensors, we further demonstrate that application of the lessons learned with DAN regioisomers to the expansion to dialkoxyanthracenes provides access to privileged amplifiers with submicromolar activity. 相似文献
72.
Concomitant Carboxylate and Oxalate Formation From the Activation of CO2 by a Thorium(III) Complex 下载免费PDF全文
Alasdair Formanuik Dr. Fabrizio Ortu Christopher J. Inman Dr. Andrew Kerridge Dr. Ludovic Castro Prof. Laurent Maron Dr. David P. Mills 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):17976-17979
Improving our comprehension of diverse CO2 activation pathways is of vital importance for the widespread future utilization of this abundant greenhouse gas. CO2 activation by uranium(III) complexes is now relatively well understood, with oxo/carbonate formation predominating as CO2 is readily reduced to CO, but isolated thorium(III) CO2 activation is unprecedented. We show that the thorium(III) complex, [Th(Cp′′)3] ( 1 , Cp′′={C5H3(SiMe3)2‐1,3}), reacts with CO2 to give the mixed oxalate‐carboxylate thorium(IV) complex [{Th(Cp′′)2[κ2‐O2C{C5H3‐3,3′‐(SiMe3)2}]}2(μ‐κ2:κ2‐C2O4)] ( 3 ). The concomitant formation of oxalate and carboxylate is unique for CO2 activation, as in previous examples either reduction or insertion is favored to yield a single product. Therefore, thorium(III) CO2 activation can differ from better understood uranium(III) chemistry. 相似文献
73.
Inside Cover: Kinetics of Reactive Modules Adds Discriminative Dimensions for Selective Cell Imaging (ChemPhysChem 10/2016) 下载免费PDF全文
74.
Ludovic Patey 《Israel Journal of Mathematics》2016,216(2):905-955
Informally, a mathematical statement is robust if its strength is left unchanged under variations of the statement. In this paper, we investigate the lack of robustness of Ramsey’s theorem and its consequence under the frameworks of reverse mathematics and computable reducibility. To this end, we study the degrees of unsolvability of cohesive sets for different uniformly computable sequence of sets and identify different layers of unsolvability. This analysis enables us to answer some questions of Wang about how typical sets help computing cohesive sets. 相似文献
75.
Luc Barbet Marc Dambrine Aris Daniilidis Ludovic Rifford 《Israel Journal of Mathematics》2016,212(2):757-790
We establish a “preparatory Sard theorem” for smooth functions with a partially affine structure. By means of this result, we improve a previous result of Rifford [17, 19] concerning the generalized (Clarke) critical values of Lipschitz functions defined as minima of smooth functions. We also establish a nonsmooth Sard theorem for the class of Lipschitz functions from Rd to Rp that can be expressed as finite selections of Ck functions (more generally, continuous selections over a compact countable set). This recovers readily the classical Sard theorem and extends a previous result of Barbet–Daniilidis–Dambrine [1] to the case p > 1. Applications in semi-infinite and Pareto optimization are given. 相似文献
76.
Richard JA Jean L Romieu A Massonneau M Noack-Fraissignes P Renard PY 《Organic letters》2007,9(23):4853-4855
A strategy involving the use of a self-immolative linker has been investigated for the chemiluminescent sensing of proteases. The reactive linker enabled the release of a 1,2-dioxetane light precursor. As a proof of principle, caspase-3, a key peptidase involved in apoptosis has been targeted. An in vitro assay has been carried out and proved the decomposition of the linker and the selectivity for caspase-3. 相似文献
77.
78.
Bitton R Berglin M Elwing H Colin C Delage L Potin P Bianco-Peled H 《Macromolecular bioscience》2007,7(12):1280-1289
Adhesive materials extracted from the brown algae Fucus Serratus were studied. These adhesives are composed of cross-linked alginate and polyphenols oxidized in the presence of KI or KBr. All formulations were capable of adhering to a variety of surfaces, however the adhesion properties were influenced by the halide used. SAXS and TEM experiments revealed that oxidized polyphenols self-assemble into chain-like objects, irrespective of the oxidation conditions. Yet, slight differences in the aggregate size were detected. QCM-D results showed that the kinetics of the oxidation was faster with iodide than with bromide. Moreover, oxidation with iodide generates stiffer networks, suggesting that the interaction between the alginate and the polyphenol could be the cause of the reduced adhesion. 相似文献
79.
Alberto Mittone Ilja Manakov Ludovic Broche Christophe Jarnias Paola Coan Alberto Bravin 《Journal of synchrotron radiation》2017,24(6):1226-1236
The detection system is a key part of any imaging station. Here the performance of the novel sCMOS‐based detection system installed at the ID17 biomedical beamline of the European Synchrotron Radiation Facility and dedicated to high‐resolution computed‐tomography imaging is analysed. The system consists of an X‐ray–visible‐light converter, a visible‐light optics and a PCO.Edge5.5 sCMOS detector. Measurements of the optical characteristics, the linearity of the system, the detection lag, the modulation transfer function, the normalized power spectrum, the detective quantum efficiency and the photon transfer curve are presented and discussed. The study was carried out at two different X‐ray energies (35 and 50 keV) using both 2× and 1× optical magnification systems. The final pixel size resulted in 3.1 and 6.2 µm, respectively. The measured characteristic parameters of the PCO.Edge5.5 are in good agreement with the manufacturer specifications. Fast imaging can be achieved using this detection system, but at the price of unavoidable losses in terms of image quality. The way in which the X‐ray beam inhomogeneity limited some of the performances of the system is also discussed. 相似文献
80.
Jonathan Tennyson Peter F. Bernath Linda R. Brown Alain Campargue Michel R. Carleer Attila G. Császár Robert R. Gamache Joseph T. Hodges Alain Jenouvrier Olga V. Naumenko Oleg L. Polyansky Laurence S. Rothman Robert A. Toth Ann Carine Vandaele Nikolai F. Zobov Ludovic Daumont Alexander Z. Fazliev Tibor Furtenbacher Iouli E. Gordon Semen N. Mikhailenko Sergei V. Shirin 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(9-10):573-596