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991.
Delugas P Filippetti A Fiorentini V Bilc DI Fontaine D Ghosez P 《Physical review letters》2011,106(16):166807
We describe the intrinsic mechanism of 2-dimensional electron confinement at the n-type SrTiO3/LaAlO3 interface as a function of the sheet carrier density n(s) via advanced first-principles calculations. Electrons localize spontaneously in Ti 3d(xy) levels within a thin (?2 nm) interface-adjacent SrTiO3 region for n(s) lower than a threshold value n(c)~10(14) cm(-2). For n(s)>n(c) a portion of charge flows into Ti 3d(xz)-d(yz) levels extending farther from the interface. This intrinsic confinement can be attributed to the interface-induced symmetry breaking and localized nature of Ti 3d t(2g) states. The sheet carrier density directly controls the binding energy and the spatial extension of the conductive region. A direct, quantitative relation of these quantities with n(s) is provided. 相似文献
992.
993.
Rachele Pucciariello Loredana Tammaro Vincenzo Villani Vittoria Vittoria 《Journal of Polymer Science.Polymer Physics》2007,45(8):945-954
Novel composites based on poly(ε‐caprolactone) (PCL) and an organically modified layer double hydroxide (LDH) obtained using the melt‐extrusion technique have been characterized through structural, thermal, and mechanical analyses. Although exfoliation has not been achieved and despite the very low content of filler (from 1 to 3% by weight), significant enhancements are obtained in the physical and mechanical properties of the composites with respect to neat PCL. As a consequence, LDHs can substitute other nanofillers, in particular, cationic clays for polymeric matrices. They can be modified by a large number of organic anions, generally more numerous than the cationic ones, and can be mixed in very simple ways with polymers. This makes such nanofillers suitable to obtain new hybrid materials for a series of applications, from active food packaging to intelligent materials for biomedical device, for example, controlled drug release. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 945–954, 2007 相似文献
994.
Marco Pagliai Marcella Iannuzzi Gianni Cardini Michele Parrinello Vincenzo Schettino 《Chemphyschem》2006,7(1):141-147
The high-pressure phase transition in the deuterated lithium hydroxide crystalline state has been studied by Car-Parrinello molecular dynamics simulations, in the constant-pressure, constant-temperature ensemble. The recently developed metadynamics approach has been applied to encourage the system to transform into different phases in an affordable simulation time. A previously not completely characterized high-pressure phase has been obtained. The structural and spectroscopic properties have been studied and compared with the neutron scattering, infrared and Raman measurements. It has been found that the calculated structure differs slightly from the experimental hypothesis, and that the presence of strong hydrogen bonds is the source of the red shift and of the characteristic features of the OD-stretching bands in both IR and Raman spectra. 相似文献
995.
996.
Pier Antonucci Antonino S. Aricò Paolo Scardi Vincenzo Antonucci 《Journal of Solid State Electrochemistry》2001,6(1):16-20
pZnCuTe thin films were prepared by electrochemical synthesis in aqueous solution. Cyclic voltammetric analysis allowed us
to single out the potential region where deposition of the species occurs. Upon annealing at 400 °C, formation of cubic ZnCuTe
was confirmed by X-ray diffraction. The patterns were modelled using a MarqX algorithm which allows direct refinement of lattice
parameters over the entire pattern instead of single-peak profile analysis.
Electronic Publication 相似文献
997.
998.
999.
Vincenzo De Toma 《Rendiconti del Circolo Matematico di Palermo》2006,55(3):398-419
In this work we prove the measurability of the ellipses’ family in the affine spaceA
3 and consequently we give its elementary measure; then we prove that also the hyperbolae’s family inA
3 is measurable and we give its elementary measure, too. 相似文献
1000.