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951.
This article is a companion paper of a previous work where we have
developed the numerical analysis of a variational model first introduced by Rudin et al. and revisited by Meyer for
removing the noise and capturing textures in an image. The basic idea in this model is
to decompose an image f into two components (u + v) and then to search for (u,v) as
a minimizer of an energy functional. The first component u belongs to BV and
contains geometrical information, while the second one v is sought in a space G
which contains signals with large oscillations, i.e. noise and textures. In Meyer carried out his study in the whole 2 and his approach is rather built on harmonic analysis tools. We place ourselves in the case of a bounded set
of 2 which is the proper setting for image processing and our approach is
based upon functional analysis arguments. We define in this context the space G, give
some of its properties, and then study in this continuous setting the energy functional
which allows us to recover the components u and v. We present some numerical
experiments to show the relevance of the model for image decomposition and for image
denoising. 相似文献
952.
The commercially available rhodium(I) complex [RhCl(CO)2]2 (1) was shown to be an effective catalyst for the reduction of carbonyls with organosilanes under mild conditions. This study focusses on the hydrosilylation of aldehydes with diphenylsilane leading to the isolation of a series of dialkoxydiphenylsilanes with low catalytic loading of complex 1. 相似文献
953.
954.
Prerna Yadav Marta Jakubaszek Prof. Dr. Bernhard Spingler Dr. Bruno Goud Dr. Gilles Gasser Prof. Dr. Felix Zelder 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(25):5717-5723
Inorganic pyrophosphate (PPi) is considered as a diagnostic marker for various diseases such as cancer and vascular calcification. PPi also plays an important preservative role as an additive E450 in foodstuff. In this work, a selective FeIII–salen-based probe for PPi is described; this probe disassembles in the presence of the target analyte into its molecular blocks, 1,2-propanediamine and 3-chloro-5-formyl-4-hydroxybenzenesulfonic acid. The latter signaling unit leads to a fluorometric response. Compared with a related prototype, the new complex shows a 2.3-times stronger emission at 500 nm and a 155-times better selectivity of PPi over adenosine triphosphate (ATP). Importantly, the new probe was successfully applied for detecting E450 in foodstuff. 相似文献
955.
Abdelrahman Hamdi Mathieu Y. Laurent Annie Hémon-Ribaud Amany S. Mostafa Mohammed A.M. Massoud Khalid B. Selim Gilles Dujardin 《Tetrahedron》2019,75(3):429-440
The asymmetric access to unreported trans 4-quinolinoxy oxaproline precursors is investigated here in a comparative way by 1,3-dipolar cycloaddition of vinyloxy quinolines with chiral α-alkoxycarbonyl aldonitrones and chiral cyclic surrogates. 相似文献
956.
957.
A. Carel N. Kwamen Gilles S. de Macedo Constanze Wiederhold Prof. Dr. Iris M. Oppel Prof. Dr. Markus Albrecht 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(17):3829-3833
The thioester moiety is introduced as a lithium binding unit for the hierarchical formation of titanium(IV) catecholate-based lithium-bridged helicates. In solution, the coordination compounds show a monomer–dimer equilibrium which —in comparison to the oxo esters— is significantly shifted towards the monomers. In addition, the influence of the thioester side chain on the dimerization behavior is investigated and an expansible/compressible molecular switch is synthesized. In the latter case expansion and compression are performed reversibly in methanol, whereas in DMSO spontaneous expansion occurs. 相似文献
958.
Angelo Frei Johannes Zuegg Alysha G. Elliott Murray Baker Stefan Braese Christopher Brown Feng Chen Christopher G. Dowson Gilles Dujardin Nicole Jung A. Paden King Ahmed M. Mansour Massimiliano Massi John Moat Heba A. Mohamed Anna K. Renfrew Peter J. Rutledge Peter J. Sadler Matthew H. Todd Charlotte E. Willans Justin J. Wilson Matthew A. Cooper Mark A. T. Blaskovich 《Chemical science》2020,11(17):4531
959.
960.
Semigroup Forum - First we give a definition of a coverage on an inverse semigroup that is weaker than the one given by Lawson and Lenz and that generalizes the definition of a coverage on a... 相似文献