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561.
Poulomi Roy Doohun Kim Indhumati Paramasivam Patrik Schmuki 《Electrochemistry communications》2009,11(5):1001-1004
In the present work we investigate the effect of TiCl4 treatments on the photoconversion efficiency of TiO2 arrays used in dye sensitized solar cell. The results clearly show that by an appropriate treatment the decoration of the TiO2 nanotube arrays with TiO2 nanocrystallites of a typical size of 3 nm can be achieved. These particles can be converted to mixture of anatase and rutile phase by annealing in air. This decoration of the TiO2 nanotubes leads to a significantly higher specific dye loading and, for certain annealing treatments, to a doubling of the solar cell efficiency (in our case from 1.9% to 3.8% of AM 1.5 conditions) can be achieved. 相似文献
562.
Erdal Dinç Dumitru Baleanu Ali Osman SolakHaslet Ek?i Remziye Güzel 《Communications in Nonlinear Science & Numerical Simulation》2012,17(2):1012-1020
The study provides a new approach to explore the existence of a nanostructure on the benzoic acid-modified glassy carbon electrode (BA-GC) system by applying factor analysis with varimax rotation of factors. The infrared spectra (IR) spectra of the bare glassy carbon electrodes (GC) and the BA-GC electrode systems with benzoic acid-nanofilm (BA-FILM) were obtained by using 10 different surface modification experiments. The IR data of the bare GC, BA-GC and BA-FILM were categorized into three series corresponding to the GC, BA-GC and BA-FILM. The factor analysis method was separately applied to each group to extract the factor loadings. By making use of these loadings, the rotated factor loadings corresponding to the first two factors were computed to estimate the relationship among and within groups. The results provided by the factor analysis method indicate the existence of the BA-FILM on the BA modified glassy carbon electrode. 相似文献
563.
How to distinguish between specular and retroconfigurations for Andreev reflection in graphene rings
We numerically investigate Andreev reflection in a graphene ring with one normal conducting and one superconducting lead by solving the Bogoliubov-de Gennes equation within the Landauer-Büttiker formalism. By tuning chemical potential and bias voltage, it is possible to switch between regimes where electron and hole originate from the same band (retroconfiguration) or from different bands (specular configuration) of the graphene dispersion, respectively. We find that the dominant contributions to the Aharonov-Bohm conductance oscillations in the subgap transport are of period h/2e in retroconfiguration and of period h/e in specular configuration, confirming the predictions obtained from a qualitative analysis of interfering scattering paths. Because of the robustness against disorder and moderate changes to the system, this provides a clear signature to distinguish both types of Andreev reflection processes in graphene. 相似文献
564.
A single pair of helical edge states as realized at the boundary of a quantum spin Hall insulator is known to be robust against elastic single particle backscattering as long as time reversal symmetry is preserved. However, there is no symmetry preventing inelastic backscattering as brought about by phonons in the presence of Rashba spin orbit coupling. In this Letter, we show that the quantized conductivity of a single channel of helical Dirac electrons is protected even against this inelastic mechanism to leading order. We further demonstrate that this result remains valid when Coulomb interaction is included in the framework of a helical Tomonaga Luttinger liquid. 相似文献
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Journal of Nonlinear Science - Exact variational integrators were exposed in the context of Lagrangian mechanics in Marsden and West (2001). These integrators sample the trajectories of holonomic... 相似文献
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