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151.
Nadini Matthieu Bongiorno Christian Rizzo Alessandro Porfiri Maurizio 《Nonlinear dynamics》2020,99(1):855-878
Nonlinear Dynamics - Many real systems can be described through time-varying networks of interactions that encapsulate information sharing between individual units over time. These interactions can... 相似文献
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The one-pot synthesis of various functionalized thieno[2,3- b]thiopyran-4-ones from readily available beta-keto epsilon-xanthyl phosphonates has been accomplished by combining a Horner-Wadsworth-Emmons olefination with a base-induced intramolecular domino cyclization/thio-Michael addition. The use of cyclic ketones in this transformation allowed a facile access to novel spiro-type thieno[2,3- b]thiopyran structures. 相似文献
154.
Dr. Matthieu Tissot Prof. Alexandre Alexakis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(34):11352-11363
The copper‐catalysed conjugate addition of trialkylaluminium and dialkylzinc reagents to polyconjugated nitroolefins (nitrodiene and nitroenyne derivatives) is reported. A reversed Josiphos ligand L7 allows for the selective 1,4‐ or 1,6‐addition with high enantioselectivities. 相似文献
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157.
The photochemical reactivity of enantiomerically pure bicyclo[3.1.0]hept-3-en-2-ones has been examined to determine whether a [2+2] cycloaddition with an alkene could be achieved without interference from a photochemically induced skeletal rearrangement. The formation of a tricyclo[5.2.0.02,5]nonan-6-one was indeed the major pathway, exclusively providing the cis-anti-cis isomer. However, the formation of norbornenones was also observed, as was stereochemical scrambling at C6 in the starting material. 相似文献
158.
Design and synthesis of a self-assembled photochemical dyad based on selective imidazole recognition
The unique recognition properties of phenanthroline-strapped zinc porphyrin 1, which displays extremely high affinity for N-unsubstituted imidazoles, has been used as the driving force for the assembly of a photochemical dyad involving a zinc(II) porphyrin as energy donor and a free base porphyrin as energy acceptor. The synthesis of the imidazole-substituted porphyrin is described together with the assembly of the dyad. (1)H NMR titrations confirm the formation of a 1/1 complex between 1 and 6, as well as insertion of the imidazole of the acceptor within the phenanthroline strap of the donor. Preliminary fluorescence quenching measurements show that efficient energy transfer occurs between the self-assembled components. 相似文献
159.
Cesar Alfaro Javier Gomez Javier M. Moguerza Javier Castillo Jose I. Martinez 《Entropy (Basel, Switzerland)》2021,23(12)
Typical applications of wireless sensor networks (WSN), such as in Industry 4.0 and smart cities, involves acquiring and processing large amounts of data in federated systems. Important challenges arise for machine learning algorithms in this scenario, such as reducing energy consumption and minimizing data exchange between devices in different zones. This paper introduces a novel method for accelerated training of parallel Support Vector Machines (pSVMs), based on ensembles, tailored to these kinds of problems. To achieve this, the training set is split into several Voronoi regions. These regions are small enough to permit faster parallel training of SVMs, reducing computational payload. Results from experiments comparing the proposed method with a single SVM and a standard ensemble of SVMs demonstrate that this approach can provide comparable performance while limiting the number of regions required to solve classification tasks. These advantages facilitate the development of energy-efficient policies in WSN. 相似文献
160.
Matthieu Faure Luc Maurette Bruno Donnadieu Guy Lavigne 《Angewandte Chemie (International ed. in English)》1999,38(4):518-522
A 97% yield of [Ru 3 (CO) 12 ] (2) in 20 minutes is obtained simply by treating [Ru(CO)3Cl2(thf)] with KOH under CO (1 atm). The reduction to Ru0 can be explained in terms of the facile reductive elimination of HCl from the transient hydrido complex 1 . Though elusive, the latter can be intercepted by olefins or alkynes to produce trappable alkyl or alkenyl complexes such as 3 and 4 .█ denotes a vacant coordination site. 相似文献