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421.
Grazia M.L. ConsoliViviana Cafiso Stefania StefaniCorrada Geraci 《Tetrahedron letters》2011,52(44):5831-5834
The first example of multivalent conjugate in which four α-l-C-fucosyl units are clustered by means of a calix[4]arene platform was designed as a new potential Pseudomonas aeruginosa biofilm inhibitor. The anti-biofilm activity of the synthesized compound (6) against PAO1 strain was assayed and it was found to be dose-dependent. The presence of the fucose cluster improves the biofilm inhibitor efficiency as proven by the lower inhibitor activity of the analogous glycyl-calix[4]arene derivative (3) lacking in the fucose moieties. 相似文献
422.
Sandra M. C. Malta Abimael F. D. Loula 《Numerical Methods for Partial Differential Equations》1998,14(4):519-548
Finite element methods are used to solve a coupled system of nonlinear partial differential equations, which models incompressible miscible displacement in porous media. Through a backward finite difference discretization in time, we define a sequentially implicit time-stepping algorithm that uncouples the system at each time-step. The Galerkin method is employed to approximate the pressure, and accurate velocity approximations are calculated via a post-processing technique involving the conservation of mass and Darcy's law. A stabilized finite element ( SUPG ) method is applied to the convection–diffusion equation delivering stable and accurate solutions. Error estimates with quasi-optimal rates of convergence are derived under suitable regularity hypotheses. Numerical results are presented confirming the predicted rates of convergence for the post-processing technique and illustrating the performance of the proposed methodology when applied to miscible displacements with adverse mobility ratios. © 1998 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 14: 519–548, 1998 相似文献
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Paolo Vacca Maria Grazia Maglione Carla Minarini Giovanna Salzillo Eugenio Amendola Dario Della Sala Alfredo Rubino 《Macromolecular Symposia》2005,228(1):263-272
In order to optimize polymer light emitting diode (PLED) performances, devices with holes injected through an Indium Tin Oxide (ITO) / Polyaniline (PANI) electrode into the polymer are much more efficient than devices fabricated with the anode made only by ITO. We demonstrated that by using doped PANI as hole injection layer in a polymer light emitting diode the manufacturing process can become simpler. Indeed, the pattern of conductive layer can be produced without ITO photolithography by UV exposition. As hole transporter layer, Poly(N-vinylcarbazole) (PVK) was spin coated over the doped PANI layer and a layer of tris (8-hydroxy) quinoline aluminum (Alq3) was then thermally evaporated so as to form the electron transport layer. To complete the device structure, Aluminum contacts were deposited onto the organic layers by vacuum evaporation at low pressure. The layers were characterized by X-ray small-angle diffraction, IR Raman and UV-Vis spectroscopies. Devices without PANI and with PANI as HIL were studied. 相似文献
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