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111.
Alexandre Marletta M.L. Vega Y. Galvão Gobato R.M. Faria 《Applied Surface Science》2010,256(10):3018-213
In this work, we have studied the surface morphology of photo-irradiated poly(p-phenylene vinylene) (PPV) thin films by using atomic force microscopy (AFM). We have analyzed the first-order statistical parameters, the height distribution and the distance between selected peaks. The second-order statistical analysis was introduced calculating the auto-covariance function to determine the correlation length between heights. We have observed that the photo-irradiation process produces a surface topology more homogeneous and isotropic such as a normal surface. In addition, the polymer surface irradiation can be used as a new methodology to obtain materials optically modified. 相似文献
112.
Back Cover: Formal Total Synthesis of Diazonamide A by Indole Oxidative Rearrangement (Chem. Eur. J. 31/2016)
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113.
We reduce the problem on multiplicities of simple subquotients in an -stratified generalized Verma module to the analogous problem for classical Verma modules. 相似文献
114.
Alexandre Turull 《Proceedings of the American Mathematical Society》2002,130(2):367-370
It has been noticed by many authors that the Schur indices of the irreducible characters of many quasi-simple finite groups are at most . A conjecture has emerged that the Schur indices of all irreducible characters of all quasi-simple finite groups are at most . We prove that this conjecture cannot be extended to the set of all finite perfect groups. Indeed, we prove that, given any positive integer , there exist irreducible characters of finite perfect groups of chief length which have Schur index .
115.
A tandem asymmetric conjugate addition-cyclopropanation was developed, in which a cyclic or linear enone was converted to a TMS-protected 3-substituted-cyclopropanol in an efficient one-pot reaction. These compounds were then selectively cleaved to yield alpha-methyl-beta-alkyl ketones, alpha-methylene-enones, or chain extended gamma-alkyl-enones. This methodology was applied to the formal total synthesis of (-)-(S,S)-clavukerin A and (+)-(R,S)-isoclavukerin. 相似文献
116.
Dupont J Fonseca GS Umpierre AP Fichtner PF Teixeira SR 《Journal of the American Chemical Society》2002,124(16):4228-4229
1-n-Butyl-3-methylimidazolium hexafluorophosphate room-temperature ionic liquid is not only suitable as a medium for the preparation and stabilization of iridium nanoparticles but also ideal for the generation of recyclable biphasic catalytic systems for hydrogenation reactions. Thus, Ir(0) nanoparticles with a mean diameter of 2 nm have been prepared by reduction of Ir(I) dissolved in the ionic liquid with H2. This catalytic solution can be reused several times for the biphasic hydrogenation of olefins under mild reaction conditions. 相似文献
117.
Bernard Coupet Hervé Gaussier Alexandre Sukhov 《Proceedings of the American Mathematical Society》1999,127(11):3191-3200
We study rigidity and regularity properties of CR maps between smooth convex hypersurfaces of finite type in
118.
Alexandre Froda 《Annali di Matematica Pura ed Applicata》1978,44(1):185-199
Résumé L’on définit, pour ρ>0 donné, des familles de para-voisinages J(J) (§ 1) des pointsJ de l’espace euclidienE
(n),continus par rapport àJ. On étudie certaines propriétés à distance, ?.-à-d. qui rattachent les valeurs de f(P) reélle, borneé, enJ et sur J(J). L’ensemble desJ est alors relativement dense enE
(n) (§ 2). Résultats pareils en renon?ant à la continuité (§ 3). 相似文献
119.
The effect of silica aerosils on the kinetics of the first-order nematic-isotropic (NI) phase transition is phenomenologically described in the framework of the time-dependent Landau-Ginzburg equation. A steady-state solution to the equation is presented such that the NI interface may propagate with a solitary-like wave profile under constant quenching. The results provide a plausible basis for the interpretation of the dynamical effects of quenched disorder in the liquid-crystal systems, caused by randomly interconnected porous media, such as aerosils. In the low silica aerosil ρs ( ≤0.1 g/cm^3) regime, the calculated values of the interface velocity v(T,ρs), the interface thickness κ(T,ρs), and the critical radius of a spherical nucleus of new nematic phase in a bulk isotropic environment, composed of polar molecules, such as 4-n-octyl- 4′- cyanobiphenyl and 4-n-heptyl- 4′- cyanobiphenyl shows that the effect of silica aerosils on the kinetics is reflected in a shifting of the set of temperature-dependent curves to lower temperature values.-1 相似文献
120.