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81.
Retsos H Gorodyska G Kiriy A Stamm M Creton C 《Langmuir : the ACS journal of surfaces and colloids》2005,21(17):7722-7725
We investigated the adhesive properties of binary heterogeneous polymer brushes made from end-functionalized polystyrene (PS) and poly(2-vinylpyridine) (P2VP) chains. The molecular organization of the mixed brush could be varied reversibly by exposure to selective solvents for PS (toluene) and for P2VP (acidic water). This exposure results in reversible switching of adhesive and wetting properties. The manner in which the adhesion switching occurs can be tuned by the composition of mixed brushes. However, the outer surface composition could be enriched more effectively in PS after the toluene treatment than in P2VP after the acidic water treatment. As a result, the mixed brush compositions that showed the largest difference in properties between an exposure to toluene and an exposure to water were the P2VP-rich compositions. Adhesive properties, tested against a soft hydrophobic pressure-sensitive adhesive (PSA) using a probe test, always showed smaller differences between solvent treatments than wetting properties with water, suggesting a much higher sensitivity of the hydrophobic/hydrophilic brushes to polar molecules than to nonpolar molecules. 相似文献
82.
Costantino Capozzoli 《Ricerche di matematica》2012,61(2):171-184
Let ?? be a bounded open subset of ${\mathbb{G}}$ , where ${\mathbb{G}}$ is a Carnot group, and let ${u: \Omega \rightarrow \mathbb{R}^d}$ be a vector valued function. We prove a lower semicontinuity result in the weak topology of the horizontal Sobolev space ${W^{1,p}_X(\Omega,\mathbb{R}^d)}$ , with p?>?1, of the integral functional of the calculus of variations of the type $$F(u)=\int\limits_\Omega f(Xu)\,dx$$ where f is a X-quasiconvex function satisfying a non-standard growth conditions and Xu is the horizontal gradient of u. 相似文献
83.
Zazza C Rutigliano M Sanna N Barone V Cacciatore M 《The journal of physical chemistry. A》2012,116(9):1975-1983
The O/β-quartz interaction is described by combining our time-dependent semiclassical approach to atom-molecule/surface scattering with first-principles electronic structure calculations at the DFT (PBE0) level of accuracy. In particular, the O, O(2) interaction potentials with an on-top Si atom and its nearest O atom both localized over three different silica clusters have been calculated as a function of the oxygen-silica approaching distance. The calculated DFT potential energy surface has been used in semiclassical trajectory calculations to investigate the sticking and inelastic reflection of oxygen atoms from a model β-quartz surface. The collisional mechanism, including the role played by the phonon dynamics, is brought to light and accurate sticking probabilities are calculated at five impact energies in the range [0.05-0.8] eV and T(S) = 1000 K. The different catalytic response of β-quartz and β-cristobobalite to the atomic oxygen flux is also discussed and highlighted. 相似文献
84.
Levenius M Conforti M Baronio F Pasiskevicius V Laurell F De Angelis C Gallo K 《Optics letters》2012,37(10):1727-1729
We theoretically and experimentally investigate multistep parametric processes in broadband optical parametric generators (OPGs) based on periodically poled 1 mol. % MgO-doped stoichiometric LiTaO3. We demonstrate that parametric collateral processes may deplete or enhance spectral portions of the OPG output, depending on pump pulse duration. 相似文献
85.
The interpretation of the violation of Bell-Clauser-Horne inequalities is revisited, in relation with the notion of extension of QM predictions to unmeasurable correlations. Such extensions are compatible with QM predictions in many cases, in particular for observables with compatibility relations
described by tree graphs. This implies classical representability of any set of correlations 〈A
i
〉, 〈B〉, 〈A
i
B〉, and the equivalence of the Bell-Clauser-Horne inequalities to a non void intersection between the ranges of values for
the unmeasurable correlation 〈A
1
A
2〉 associated to different choices for B. The same analysis applies to the Hardy model and to the “perfect correlations” discussed by Greenberger, Horne, Shimony
and Zeilinger. In all the cases, the dependence of an unmeasurable correlation on a set of variables allowing for a classical
representation is the only basis for arguments about violations of locality and causality. 相似文献
86.
The use of tetraphosphonic building blocks for the preparation of inorganic-organic zirconium derivatives has led to the formation of novel compounds with a modular structure. This is based on the different connection of polymeric 1D inorganic units covalently connected by organic groups. The different kinds of connections generate two different open-framework structures. These structures have been solved "ab initio" by powder X-ray diffraction data. Very likely, the dimensions of the channels inside these structures may be tuned by the right choice of the interlinking organic group. 相似文献
87.
Francesca Bellezza Antonio Cipiciani Umberto Costantino Fabio Marmottini Maria Anna Quotadamo 《Colloid and polymer science》2006,285(1):19-25
Non-ionic water-in-oil (w/o) microemulsions of pentaoxyethylenenonylphenyl ether (Igepal-CO520)/cyclohexane/water at 25 °C have been used as reaction vessels to obtain zirconium hydrogen phosphate nanoparticles. 相似文献
88.
Gianfranco Cariolaro Mauro Fregolent Alessandro Tonello Costantino De angelis 《Optical and Quantum Electronics》2004,36(10):853-880
Chirped Hermite–Gaussian functions shows outstanding potentialities in mathematical models for linear and non linear pulse propagation in optical fibers. We propose three generalized subclasses of Hermite–Gaussian functions as natural extension to the complex domain. We exemplify the properties of these subclasses by analyzing some relevant cases of pulse oscillatory dynamics governed by nonlinear Schrödinger equation with constant or periodic coefficfients. 相似文献
89.
Marco Radi Gian Paolo ValleriniAlessia Petrelli Paolo VincettiGabriele Costantino 《Tetrahedron letters》2013
A fast, versatile and practical one-pot, two-step microwave-assisted protocol for the direct synthesis of N1-substituted 5,6-ring-fused 2-pyridones has been developed. The present method proved to be effective on a series of commercially available aldehydes, ketones and amines and could be profitably exploited in drug-discovery settings for the rapid identification of biologically relevant hit compounds. 相似文献
90.
Andrea R. Costantino Romina A. Ocampo María G. Montiel Schneider Gustavo Fernandez Liliana C. Koll 《合成通讯》2013,43(23):3192-3202
A systematic study for esterification procedures to the synthesis of BINOL diesters is described. Reaction conditions with trifluoracetic acid anhydride (TFAA) and 85% H3PO4 were selected as the best procedure to prepare enantiomerically pure (S)-1,1′-bi-2-naphthol (BINOL) diesters VIII to XI with almost quantitative yields and very short reaction times. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resources: Full experimental and spectral details.] 相似文献