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101.
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Angel Contreras-García Carmen Alvarez-Lorenzo Angel Concheiro Emilio Bucio 《Radiation Physics and Chemistry》2010,79(5):615-621
Simultaneous grafting of N-isopropylacrylamide (NIPAAm) and N-(3-aminopropyl) methacrylamide hydrochloride (APMA) on polypropylene (PP) was investigated for obtaining interfaces that are stimuli-responsive under physiological conditions. A pre-irradiation method was optimized tuning the γ-irradiation dose, reaction time, temperature, and monomers concentrations. FT-IR ATR and XPS analysis of the grafted copolymers evidenced a greater content in NIPAAm than in APMA; the APMA/NIPAAm ratio increasing with the concentration of APMA in the reaction medium and when the grafting was carried out in 1 M NaNO3. The grafted films were characterized regarding their thermal properties (DSC and TGA) swelling behavior and contact angle. Immersion of the pre-irradiated films in 1 M NIPAAm/0.5 M APMA aqueous solution rendered PP-g-(1NIPAAm-r-0.5APMA) which exhibited rapid and reversible transitions showing a LCST around the physiological temperature. By contrast, a greater content in APMA enhanced the hydrophilicity and prevented the shrinking of PP-g-(1NIPAAm-r-1APMA). 相似文献
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Sanjurjo Emilio Naya Miguel Ángel Blanco-Claraco José Luis Torres-Moreno José Luis Giménez-Fernández Antonio 《Nonlinear dynamics》2017,88(3):1935-1951
Nonlinear Dynamics - Multibody simulations are already used in many industries to speed up the development of new products. However, improvements in multibody formulations and the continuous... 相似文献
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Catalytic Asymmetric Reactions of 4‐Substituted Indoles with Nitroethene: A Direct Entry to Ergot Alkaloid Structures 下载免费PDF全文
Simone Romanini Emilio Galletti Dr. Lorenzo Caruana Prof. Andrea Mazzanti Prof. Fahmi Himo Dr. Stefano Santoro Prof. Mariafrancesca Fochi Prof. Luca Bernardi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(49):17578-17582
A domino Friedel–Crafts/nitro‐Michael reaction between 4‐substituted indoles and nitroethene is presented. The reaction is catalyzed by BINOL‐derived phosphoric acid catalysts, and delivers the corresponding 3,4‐ring‐fused indoles with very good results in terms of yields and diastereo‐ and enantioselectivities. The tricyclic benzo[cd]indole products bear a nitro group at the right position to serve as precursors of ergot alkaloids, as demonstrated by the formal synthesis of 6,7‐secoagroclavine from one of the adducts. DFT calculations suggest that the outcome of the reaction stems from the preferential evolution of a key nitronic acid intermediate through a nucleophilic addition pathway, rather than to the expected “quenching” through protonation. 相似文献
107.
Rajat Kumar Pal Kamran Haider Divya Kaur William Flynn Junchao Xia Ronald M Levy Tetiana Taran Lauren Wickstrom Tom Kurtzman Emilio Gallicchio 《Journal of computer-aided molecular design》2017,31(1):29-44
As part of the SAMPL5 blinded experiment, we computed the absolute binding free energies of 22 host–guest complexes employing a novel approach based on the BEDAM single-decoupling alchemical free energy protocol with parallel replica exchange conformational sampling and the AGBNP2 implicit solvation model specifically customized to treat the effect of water displacement as modeled by the Hydration Site Analysis method with explicit solvation. Initial predictions were affected by the lack of treatment of ionic charge screening, which is very significant for these highly charged hosts, and resulted in poor relative ranking of negatively versus positively charged guests. Binding free energies obtained with Debye–Hückel treatment of salt effects were in good agreement with experimental measurements. Water displacement effects contributed favorably and very significantly to the observed binding affinities; without it, the modeling predictions would have grossly underestimated binding. The work validates the implicit/explicit solvation approach employed here and it shows that comprehensive physical models can be effective at predicting binding affinities of molecular complexes requiring accurate treatment of conformational dynamics and hydration. 相似文献
108.
We consider the integral functional
under non-standard growth assumptions that we call p(x) type: namely, we assume that
a relevant model case being the functional
Under sharp assumptions on the continuous function p(x)>1 we prove regularity of minimizers. Energies exhibiting this growth appear in several models from mathematical physics.
Accepted July 13, 2000?Published online January 22, 2001 相似文献
109.
Francesco dellIsola Emilio Turco Anil Misra Zacharias Vangelatos Costas Grigoropoulos Vasileia Melissinaki Maria Farsari 《Comptes Rendus Mecanique》2019,347(5):397-405
In this paper, we reveal that the mathematical discrete model of Hencky type, introduced in [1], is appropriate for describing the mechanical behavior of micro-metric pantographic elementary modules. This behavior does not differ remarkably from what has been observed for milli-metric modules, as we prove with suitably designed experiments. Therefore, we conclude that the concept of pantographic microstructure seems feasible for micro-metrically architected microstructured (meta)materials as well. These results are particularly indicative of the possibility of fabricating materials that can have an underlying pantographic microstructure at micrometric scale, so that its unique behavior can be exploited in a larger range of technological applications. 相似文献
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