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941.
Maurice Dörr Sebastian Lips Prof. Dr. Carlos Alberto Martínez-Huitle Dr. Dieter Schollmeyer Prof. Dr. Robert Franke Prof. Dr. Siegfried R. Waldvogel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(33):7835-7838
We report an innovative, sustainable and straightforward protocol for the synthesis of N,N-diarylamides equipped with nonprotected hydroxyl groups by using electrosynthesis. The concept allows the application of various substrates furnishing diarylamides with yields up to 57 % within a single and direct electrolytic protocol. The method is thereby easy to conduct in an undivided cell with constant current conditions offering a versatile and short-cut alternative to conventional pathways. 相似文献
942.
Carlos García-Martínez Fred Glover Francisco J. Rodriguez Manuel Lozano Rafael Martí 《Computational Optimization and Applications》2014,58(1):161-185
The quadratic multiple knapsack problem (QMKP) consists in assigning a set of objects, which interact through paired profit values, exclusively to different capacity-constrained knapsacks with the aim of maximising total profit. Its many applications include the assignment of workmen to different tasks when their ability to cooperate may affect the results. Strategic oscillation (SO) is a search strategy that operates in relation to a critical boundary associated with important solution features (such as feasibility). Originally proposed in the context of tabu search, it has become widely applied as an efficient memory-based methodology. We apply strategic oscillation to the quadratic multiple knapsack problem, disclosing that SO effectively exploits domain-specific knowledge, and obtains solutions of particularly high quality compared to those obtained by current state-of-the-art algorithms. 相似文献
943.
Oksana Kharchenko Vitaliy Smokal Oksana Krupka Pavlo Virych Natalia Kutsevol 《Molecular Crystals and Liquid Crystals》2020,699(1):51-56
AbstractThe thermostability of polysterene with/without new styrylquinoline containing methacrylic fragments has been described in the present work. Polystyrene and copolymers based on styrene and new methacrylic styrylquinoline containing monomers were synthesized by free radical thermoinitiated polymerization in the presence of 2,2′-azobisisobutyronitrile (1?wt%) as initiator at inert atmosphere. The impact of 2-[2-(4-methoxyphenyl)ethenyl]quinolin-8-yl 2-methylpropyl-2-enoate (М1), 2-(2-phenylethenyl)quinolin-8-yl 2-methylpropyl-2-enoate (М2), 2-[2-(4-nitrophenyl)ethenyl]quinolin-8-yl 2-methylpropyl-2-enoate (М3) on thermal stability of polystyrene was investigated. The thermostability of polystyrene and copolymers ST:M1, ST:M2, ST:M3 were studied by dynamic thermograviametric analysis. It was shown that destruction of polystyrene with corresponding units M1-M2 starts at 41–42°С higher, than reference polystyrene. 相似文献
944.
945.
Hexametaphosphate‐Capped Silica Mesoporous Nanoparticles Containing CuII Complexes for the Selective and Sensitive Optical Detection of Hydrogen Sulfide in Water
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Sameh El Sayed Dr. Michele Milani Prof. Maurizio Licchelli Prof. Ramón Martínez‐Máñez Dr. Félix Sancenón 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(19):7002-7006
CuII‐macrocycle functionalized hexametaphosphate‐capped silica mesoporous nanoparticles have been prepared and used for the selective and sensitive detection of hydrogen sulfide in aqueous environments. The possibility of using different metal complexes combined with different capping anions and choice of different dyes or other sensing molecules as indicators makes this new protocol highly appealing for the preparation of new sensing systems for sulfide detection in different environments. 相似文献
946.
947.
External electric field effect on electronic properties and charge transfer in CoI2/NiI2 spinterface
Iuliia Melchakova Evgenia A. Kovaleva Natalia S. Mikhaleva Felix N. Tomilin Sergey G. Ovchinnikov Alexander A. Kuzubov Paul Avramov 《International journal of quantum chemistry》2020,120(3):e26092
Electronic structure and spin-related properties of CoI2/NiI2 heterostructure were studied by means of density functional theory. It was shown that the electronic structure at the Fermi level can be characterized by a band gap. The effect of the external electric field on charge transfer and electronic properties of the CoI2/NiI2 interface was investigated, and it was found that band gap width depends on the strength of the applied electric field, switching its nature from semiconducting to a half-metallic one. An easy control of the electronic properties and promising spin-polarized nature of the CoI2/NiI2 spinterface allows the heterostructure to be used in spin-related applications. 相似文献
948.
Cover Picture: A Versatile Approach to CF3‐Containing 2‐Pyrrolidones by Tandem Michael Addition–Cyclization: Exemplification in the Synthesis of Amidine Class BACE1 Inhibitors (Chem. Eur. J. 33/2015)
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949.
950.
Elías-Zúñiga Alex Palacios-Pineda Luis Manuel Olvera-Trejo Daniel Martínez-Romero Oscar 《Nonlinear dynamics》2020,102(3):1239-1270
Nonlinear Dynamics - In this paper, the dynamics response of a finite extensibility nonlinear elastic (FENE) absorber attached to a nonlinear primary system is investigated by writing the modal... 相似文献