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31.
The phenomena of the spin-Hall effect, initially proposed over three decades ago in the context of asymmetric Mott skew scattering, was revived recently by the proposal of a possible intrinsic spin-Hall effect originating from a strongly spin-orbit coupled band structures. This new proposal has generated an extensive debate and controversy over the past 2 years. On August 2006 the first workshop on the spin-Hall effect was held at the Asian Pacific Center for Theoretical Physics. Its purpose was to bring together many of the leading groups in this field to resolve such issues and identify future challenges. We offer this short summary to clarify formerly controversial issues now settled and help refocus the research efforts in new and important avenues. 相似文献
32.
This paper summarizes the main results presented by the author in his PhD thesis (Montoya-Torres 2005), supervised by Stéphane
Dauzèere-Pérés, Jean-Pierre Campagne and Hélène Marian, and defended on 29 November 2005 at the école des Mines de Saint-étienne
and Université Jean-Monnet. The thesis is written in French and is available upon request from the author. This work deals
with a real-life transportation problem in the semiconductor industry. It proposes a new approach by integrating tactical
and operational decisions for the control of the automated transport system. At the tactical level, the problem is modeled
using integer linear programming models inspired from Location Theory. At the operational level, the solution obtained from
the tactical optimization is coupled with a discrete-event computer simulation program and some policies for transportation
operations are implemented and compared. 相似文献
33.
Juliana Nanclares Jesús Gil Benjamn Rojano Jairo Saez Bernd Schneider Felipe Otlvaro 《Tetrahedron letters》2008,49(24):3844-3847
4-Methoxy-1H-phenalen-1-one (4-methoxyperinaphthenone, 1), a subunit found in some Musa phytoalexins and related natural products from the Haemodoraceae, was synthesized starting from 2-methoxynaphthalene in five steps and an overall yield of 36%. A Heck–Fujiwara coupling between ethyl acrylate and 1-bromonaphthalene afforded the corresponding (E)-naphthylpropanoic acid which, after hydrogenolysis, was subjected to a one-pot Friedel–Crafts acylation–DDQ dehydrogenation procedure to furnish 1. 相似文献
34.
35.
König M Tschetschetkin A Hankiewicz EM Sinova J Hock V Daumer V Schäfer M Becker CR Buhmann H Molenkamp LW 《Physical review letters》2006,96(7):076804
Ring structures fabricated from HgTe/HgCdTe quantum wells have been used to study Aharonov-Bohm type conductance oscillations as a function of Rashba spin-orbit splitting strength. We observe nonmonotonic phase changes indicating that an additional phase factor modifies the electron wave function. We associate these observations with the Aharonov-Casher effect. This is confirmed by comparison with numerical calculations of the magnetoconductance for a multichannel ring structure within the Landauer-Büttiker formalism. 相似文献
36.
37.
Mašek J Máca F Kudrnovský J Makarovsky O Eaves L Campion RP Edmonds KW Rushforth AW Foxon CT Gallagher BL Novák V Sinova J Jungwirth T 《Physical review letters》2010,105(22):227202
We analyze microscopically the valence and impurity band models of ferromagnetic (Ga,Mn)As. We find that the tight-binding Anderson approach with conventional parametrization and the full potential local-density approximation+U calculations give a very similar band structure whose microscopic spectral character is consistent with the physical premise of the k·p kinetic-exchange model. On the other hand, the various models with a band structure comprising an impurity band detached from the valence band assume mutually incompatible microscopic spectral character. By adapting the tight-binding Anderson calculations individually to each of the impurity band pictures in the single Mn impurity limit and then by exploring the entire doping range, we find that a detached impurity band does not persist in any of these models in ferromagnetic (Ga,Mn)As. 相似文献
38.
39.
Jairo E. Castellanos Paulo D. Cordaro Gerson Petronilho 《Journal d'Analyse Mathématique》2013,119(1):333-364
In this work, we introduce the notion of s-Gevrey vectors in locally integrable structures of tube type. Under the hypothesis of analytic hypoellipticity, we study the Gevrey regularity of such vectors and also show how this notion can be applied to the study of the Gevrey regularity of solutions of certain classes of semilinear equations. 相似文献
40.
Andréa Silva Garcia de Figueiredo-Rinhel Micássio Fernandes de Andrade Ana Paula Landi-Librandi Ana Elisa Caleiro Seixas Azzolini Luciana Mariko Kabeya Jairo Kenupp Bastos 《Natural product research》2019,33(17):2521-2525
The aerial parts of Baccharis dracunculifolia (BdE) is used in the Brazilian folk medicine to treat inflammatory conditions. Here we examined the ability of free and liposomal BdE to modulate reactive oxygen species generation in human neutrophils in vitro and zymosan-induced acute joint inflammation in Wistar rats. We prepared biocompatible liposomes of soya phosphatidylcholine and cholesterol with low diameter, homogeneous size distribution, and neutral surface charge. Free BdE decreased joint swelling, total leucocyte and neutrophil infiltration, and the synovial levels of tumour necrosis factor-α and interleukins 6 and 1β. Incorporation of BdE into liposomes preserved its capacity to inhibit the neutrophil superoxide anion and total reactive oxygen species generation, and improved its anti-inflammatory effect in vivo by decreasing the effective BdE dose by nearly sixfold. The same liposome type lowered the effective dose of caffeic acid by nearly sixteenfold. Therefore, incorporation of BdE into phosphatidylcholine-cholesterol liposomes improves its anti-inflammatory effect. 相似文献