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21.
K. C. Nicolaou Dionisios Vourloumis Tianhu Li Joaquin Pastor Nicolas Winssinger Yun He Sacha Ninkovic Francisco Sarabia Hans Vallberg Frank Roschangar N. Paul King M. Ray V. Finlay Pareskevi Giannakakou Pascal Verdier-Pinard Ernest Hamel 《Angewandte Chemie (International ed. in English)》1997,36(19):2097-2103
22.
When a stretched elastomer is laminated to a flat plastic frame, a complex shape is formed, which is termed a minimum-energy structure. It is shown how self-organized structures can be applied in the development of actuators with complex, out-of-plane actuationmodes. This unusual concept is then demonstrated in the case of dielectric elastomer actuators. Among advantages of this approach are the simplicity in manufacturing, the potential complexity and sophistication of the manufactured structures, and the general benefits of the concept when applied to other electro-mechanically active materials. PACS 46.32.+x; 77.65.-j; 83.80.Va 相似文献
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The Conder and Young (CY) and the peak maximum (PM) methods were used to estimate the retention time of n-alkane probes on chemithermomechanical pulp (CTMP) wood fibers treated with a low molecular weight grade phenol-formaldehyde resin (PFR). Thermodynamic functions (ΔHao, ΔGao, and ΔSao) and the London dispersive component of the surface energy were derived from these retention times. Treated wood fibers show a high energy surface due to the presence of the thermoset resin on their surface. Values of ΔHao obtained from the CY method were higher than those obtained with the PM method at relatively high temperatures and with relatively low molecular weight alkanes. The results from the two methods were identical at low temperature (293 K) and with the relatively high molecular weight alkane n-undecane. 相似文献
27.
Let be a strongly Lipschitz domain of (n?2). We give endpoint versions of div–curl lemmata on , for a given function f on whose gradient belongs to a Hardy space on . To cite this article: P. Auscher et al., C. R. Acad. Sci. Paris, Ser. I 337 (2003). 相似文献
28.
Michaël Lejeune Andrea Valsesia Martin Kormunda Pascal Colpo François Rossi 《Surface science》2005,583(1):L142
In this work, chemically and topographically nanopatterned surfaces were produced by a top-down processing approach for biosensing devices. The nanopatterning was the result of the combination of plasma polymerisation (pp) of biofunctional materials and colloidal lithography techniques. The morphological and chemical properties induced by the plasma deposition-etching treatment were characterised by optical method combining ellipsometry and Fourier Transform Infrared spectroscopy studies. This method supported by atomic force microscopy measurements, allowed the full optical characterization of each step of the top-down process. The optical characterization of the end-up nanopatterned samples demonstrated that the chosen process is able to produce well-defined nanostructured surfaces with controlled chemical and morphological properties. 相似文献
29.
Marc Visseaux Mickael Terrier Andr Mortreux Pascal Roussel 《Comptes Rendus Chimie》2007,10(12):1195-1199
The reaction of one equivalent of Nd(BH4)3(THF)3 with an half equivalent of dialkylmagnesium in the presence of a stoichiometric amount of pentamethylcyclopentadiene cleanly affords a new kind of half-sandwich of neodymium that is stable toward comproportionation. This strategy can be advantageously applied to generate in situ catalysts allowing the controlled polymerisation of isoprene. 相似文献
30.
S. Mathias M. Wessendorf S. Passlack M. Aeschlimann M. Bauer 《Applied Physics A: Materials Science & Processing》2006,82(3):439-445
Epitaxial ultra-thin Ag films grown on Cu(111) have been investigated by angle-resolved photoemission spectroscopy. The thickness
dependence of the binding energy for the Shockley surface state at 300 K could be determined accurately in films up to 5 ML
thick. Furthermore, we observe drastic changes in the film morphology after annealing to 450 K. Spectral modifications in
the shape of the quantum-well states (QWS), characteristic for these ultra-thin silver films, prove that the surface morphology
is homogeneous. The photoemission spectra also indicate that the silver film bifurcates to form a film exhibiting two distinct
film thicknesses. For all levels of silver coverage, we identify surface regions that are 2 ML thick, while the thickness
of the remaining surface depends on the amount of deposited silver. The almost purely Lorentzian line-shape of the spectral
features corresponding to the two different surface regions show that both surface areas are atomically flat.
PACS 68.55.Jk; 73.20.At; 73.21.Fg; 79.60.Dp 相似文献