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21.
Hybrid SiO2-TiO2 films are prepared starting from tetraisopropoxy titanate and 3-glycidoxipropyltrimethoxysilane, using the sol-gel process. During the sol synthesis titania clusters grow, conferring to the samples a photocatalytic activity. In this paper we exploit this property for the fabrication of surface-relief gratings. The realized structures are characterized by SEM, AFM and profilometric measurements, while the presence of titania clusters is confirmed by TEM analyses.  相似文献   
22.
A hit optimization protocol applied to the first nonnucleoside inhibitor of the ATPase activity of human DEAD-box RNA helicase DDX3 led to the design and synthesis of second-generation rhodanine derivatives with better inhibitory activity toward cellular DDX3 and HIV-1 replication. Additional DDX3 inhibitors were identified among triazine compounds. Biological data were rationalized in terms of structure-activity relationships and docking simulations. Antiviral activity and cytotoxicity of selected DDX3 inhibitors are reported and discussed. A thorough analysis confirmed human DDX3 as a valid anti-HIV target. The compounds described herein represent a significant advance in the pursuit of novel drugs that target HIV-1 host cofactors.  相似文献   
23.
24.
In this paper, we propose a local projection stabilization (LPS) finite element method applied to numerically solve natural convection problems. This method replaces the projection-stabilized structure of standard LPS methods by an interpolation-stabilized structure, which only acts on the high frequencies components of the flow. This approach gives rise to a method which may be cast in the variational multi-scale framework, and constitutes a low-cost, accurate solver (of optimal error order) for incompressible flows, despite being only weakly consistent. Numerical simulations and results for the buoyancy-driven airflow in a square cavity with differentially heated side walls at high Rayleigh numbers (up to \(Ra=10^7\)) are given and compared with benchmark solutions. Good accuracy is obtained with relatively coarse grids.  相似文献   
25.
Various realizations of variational multiscale (VMS) methods for simulating turbulent incompressible flows have been proposed in the past fifteen years. All of these realizations obey the basic principles of VMS methods: they are based on the variational formulation of the incompressible Navier–Stokes equations and the scale separation is defined by projections. However, apart from these common basic features, the various VMS methods look quite different. In this review, the derivation of the different VMS methods is presented in some detail and their relation among each other and also to other discretizations is discussed. Another emphasis consists in giving an overview about known results from the numerical analysis of the VMS methods. A few results are presented in detail to highlight the used mathematical tools. Furthermore, the literature presenting numerical studies with the VMS methods is surveyed and the obtained results are summarized.  相似文献   
26.
意大利著名设计师Stefano Giovannoni不久前将一个旧工厂的厂房改建成居家与办公相结合的空间。项目的地点在米兰ViaTortona区附近。改建完成之后,由于其在建筑与室内设计上的特殊性,这个房子几乎成了展览及各类活动的举办地,尤其是salone国际设计周期间,这里更是热闹非凡。  相似文献   
27.
[Zn(4-mbzdtc)2] (1), [Zn(4-mbzdtc)2(py)] (2), [Zn2(4-mbzdtc)4(4,4′-bipy)] (3), and [Zn(4-mbzdtc)2(2,2′-bipy)] (4), (where, 4-mbzdtc?=?N,N-di(4-methoxybenzyl)dithiocarbamate) were prepared and characterized by elemental analysis, infrared, 1H and 13C NMR spectroscopy and the structures of 1 and 3 were elucidated by X-ray crystallography. The monomeric structure of 1 shows a distorted tetrahedral geometry for zinc(II). The coordination geometry around zinc in dinuclear complex 3 is an intermediate between square pyramidal and trigonal bipyramidal. The downfield shift of NCS2 carbon signal for imine adducts of 24 compared to those found in parent complex 1 is attributed to the change in coordination number and steric effect exerted by the nitrogen donor ligand. Hirshfeld surface analysis was used to visualize intermolecular interactions in the crystal structure of 1 and 3. The geometry optimization of 1 is performed using DFT with the B3LYP-LANL2DZ basis set. Solvothermal decomposition of 1 yielded only hexagonal zinc sulfide nanoparticles. Zinc sulfide nanoparticles were characterized using powder X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectra and diffuse reflectance spectra. DRS study of ZnS nanoparticles shows the quantum confinement effect with a band gap of 3.74?eV.  相似文献   
28.
In the past few years detection of repeatable and distinctive keypoints on 3D surfaces has been the focus of intense research activity, due on the one hand to the increasing diffusion of low-cost 3D sensors, on the other to the growing importance of applications such as 3D shape retrieval and 3D object recognition. This work aims at contributing to the maturity of this field by a thorough evaluation of several recent 3D keypoint detectors. A categorization of existing methods in two classes, that allows for highlighting their common traits, is proposed, so as to abstract all algorithms to two general structures. Moreover, a comprehensive experimental evaluation is carried out in terms of repeatability, distinctiveness and computational efficiency, based on a vast data corpus characterized by nuisances such as noise, clutter, occlusions and viewpoint changes.  相似文献   
29.
Abrouq号,这艘华丽的游船是由意大利比萨的一家造船所受中东某国的委托而设计的,主要用于在波斯湾海区的游览娱乐。室内设计由Ivana Porfiri设计完成,Ivana Porfiri是近年来在豪华游船室内设计上具有丰富经验的专业设计师。  相似文献   
30.
Open cell foams obtained by the simultaneous coreaction of condensed flavonoid tannins with an alkoxylated fatty amine and polymeric diphenylmethane isocyanate yielded highly flexible/elastic polyurethane foams. Copolymerized amine/isocyanate/tannin oligomers were identified by 13C NMR and MALDI‐TOF spectroscopy. In general, between 30% and 50% of natural tannins is added to the components used to obtain polymerisation of the polyurethane. The characteristic of these new, partially biosourced polyurethanes is that the tannin present slows down burning, some of them can be made flame self‐extinguishing and if burning they neither flow nor asperge flaming material around, contrary to what occurs with normal polyurethanes. This limits the possibility of transmitting fire to other materials in the same environment. Cyclic compression tests were carried out showing that after 50 cycles foam recovery was in excess of 80%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40499.  相似文献   
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