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Sara Cruz?y?Cruz Oscar Rosas-Ortiz 《International Journal of Theoretical Physics》2011,50(7):2201-2210
The Schr?dinger equation for position-dependent mass singular oscillators is solved by means of the factorization method and
point transformations. These systems share their spectrum with the conventional singular oscillator. Ladder operators are
constructed to close the su(1,1) Lie algebra and the involved point transformations are shown to preserve the structure of the Barut-Girardello and Perelomov
coherent states. 相似文献
75.
Cláudia A. Kodaira Ana Valéria S. Lourenço Maria Cláudia F.C. Felinto Eduardo M.R. Sanchez Francisco J.O. Rios Luiz Antonio O. Nunes Magnus Gidlund Oscar L. Malta Hermi F. Brito 《Journal of luminescence》2011,131(4):727-731
Neodymium based fluorescence presents several advantages in comparison to conventional rare earth or enzyme-substrate based fluorescence emitting sources (e.g.Tb, HRP) . Based on this fact we have herein explored a Nd-based fluoroimmunoassay. We efficiently detected the presence of an oxidized low-density lipoprotein (oxLDL) in human plasma a well-known marker for cardiovascular diseases, which causes around 30% of deaths worldwide. Conventional fluoroimmunoassay uses time-resolved luminescence techniques, with detection in the visible range, to eliminate the fluorescence background from the biological specimens. By using an immunoassay based on functionalized Y2O3:Nd3+ nanoparticles, where the excitation and emission processes in the Nd3+ ion occur in the near-infrared (NIR) region, we have succeeded in eliminating the interferences from the biological fluorescence background, avoiding the use of time-resolved techniques. This yields higher emission intensity from the Nd3+-nanolabels and efficient detection of anti-oxidized low-density lipoproteins (anti-oxLDL) by Y2O3:Nd3+-antibody-antigen conjugation, leading to a novel biolabeling method. 相似文献
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Javier Mazuela Oscar Pàmies Montserrat Diéguez Laetitia Palais Stephane Rosset Alexandre Alexakis 《Tetrahedron: Asymmetry》2010,21(17):2153-2157
A biaryl-based monophosphoroamidite L1–L4a–f and aminophosphine L5–L7a–f ligand library was screened in the Rh-catalyzed asymmetric hydroformylation of several vinylarenes and heterocyclic olefins. Our results indicate that the selectivity is strongly dependent on the ligand parameters and on the substrate type. Enantioselectivities (up to 46%) were moderate in the hydroformylation of several vinylarenes S1–S5 and promising (up to 58%) for the more challenging heterocyclic olefins S6–S9. 相似文献
78.
The present paper deals with the formulation of minimal loading conditions for the application of numerical homogenisation techniques, namely the FE2 methodology. Based on the set of volume averaging rules connecting the heterogeneous micro and the homogeneous macro scale, the minimal constraints on the deformation of a micro volume are derived for a classical Cauchy continuum as well as for a micromorphic continuum theory. For both cases, numerical studies are included highlighting the main aspects of the proposed procedure within the context of small deformations. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
79.
Michael Dmling Merle Arrowsmith Uwe Schmidt Luis Werner Abril C. Castro J. Oscar C. Jimnez‐Halla Rüdiger Bertermann Jonas Müssig Dominic Prieschl Holger Braunschweig 《Angewandte Chemie (International ed. in English)》2019,58(29):9782-9786
The transfer hydrogenation of N‐heterocyclic carbene (NHC)‐supported diborenes with dimethylamine borane proceeds with high selectivity for the trans‐1,2‐dihydrodiboranes. DFT calculations, supported by kinetic studies and deuteration experiments, suggest a stepwise proton‐first‐hydride‐second reaction mechanism via an intermediate μ‐hydrodiboronium dimethylaminoborate ion pair. 相似文献
80.
Oscar Bolina Pierluigi Contucci Bruno Nachtergaele Shannon Starr 《Communications in Mathematical Physics》2000,212(1):63-91
We show that the ground states of the three-dimensional XXZ Heisenberg ferromagnet with a 111 interface have excitations localized in a subvolume of linear size R with energies bounded by O(1/R2). As part of the proof we show the equivalence of ensembles for the 111 interface states in the following sense: In the thermodynamic limit the states with fixed magnetization yield the same expectation values for gauge invariant local observables as a suitable grand canonical state with fluctuating magnetization. Here, gauge invariant means commuting with the total third component of the spin, which is a conserved quantity of the Hamiltonian. As a corollary of equivalence of ensembles we also prove the convergence of the thermodynamic limit of sequences of canonical states (i.e., with fixed magnetization). 相似文献