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91.
Scattering spherical voids in nanocrystalline TiO2- enhancement of efficiency in dye-sensitized solar cells 总被引:1,自引:0,他引:1
Hore S Nitz P Vetter C Prahl C Niggemann M Kern R 《Chemical communications (Cambridge, England)》2005,(15):2011-2013
Spherical voids as light scattering centers in nanocrystalline TiO2 films were realized with polystyrene particles of diameter 400 nm, thus enhancing the photovoltaic performance by 25% on large areas, as well as providing an indication that these films can be used with electrolytes of higher viscosity. 相似文献
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We study the multiplicative properties of the dual of Lusztig's semicanonical basis. The elements of this basis are naturally indexed by the irreducible components of Lusztig's nilpotent varieties, which can be interpreted as varieties of modules over preprojective algebras. We prove that the product of two dual semicanonical basis vectors ρZ′ and ρZ″ is again a dual semicanonical basis vector provided the closure of the direct sum of the corresponding two irreducible components Z′ and Z″ is again an irreducible component. It follows that the semicanonical basis and the canonical basis coincide if and only if we are in Dynkin type An with n?4. Finally, we provide a detailed study of the varieties of modules over the preprojective algebra of type A5. We show that in this case the multiplicative properties of the dual semicanonical basis are controlled by the Ringel form of a certain tubular algebra of type (6,3,2) and by the corresponding elliptic root system of type . 相似文献
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The dispersed fluorescence spectrum of the ground electronic state of thiophosgene, SCCl2, is analyzed in a very complex region of vibrational excitation, 7000-9000 cm(-1). The final result is that most of the inferred excited vibrational levels are assigned in terms of approximate constants of the motion. Furthermore, each level is associated with a rung on a ladder of quantum states on the basis of common reduced dimension fundamental motions. The resulting ladders cannot be identified by any experimental means, and it is the interspersing in energy of their rungs that makes the spectrum complex even after the process of level separation into polyads. Van Vleck perturbation theory is used to create polyad constants of the motion and a spectroscopic Hamiltonian from a potential fitted to experimental data. The eigen functions of this spectroscopic Hamiltonian are rewritten as semiclassical wave functions and transformed to a representation that allows us to analyze and assign the spectra with no other work other than to utilize concepts from nonlinear dynamics. 相似文献
97.
Bai J Cui LF Wang J Yoo S Li X Jellinek J Koehler C Frauenheim T Wang LS Zeng XC 《The journal of physical chemistry. A》2006,110(3):908-912
Results of a combined photoelectron spectroscopy and first-principles density-functional study of SiN- clusters in the size range 20 or= 20. For 28 相似文献
98.
Gattringer C 《Physical review letters》2006,97(3):032003
We represent Polyakov loops and their correlators as spectral sums of eigenvalues and eigenmodes of the lattice Dirac operator. The deconfinement transition of pure gauge theory is characterized as a change in the response of moments of eigenvalues to varying the boundary conditions of the Dirac operator. We argue that the potential between static quarks is linked to spatial correlations of Dirac eigenvectors. 相似文献
99.
El Gabaly F Gallego S Muñoz C Szunyogh L Weinberger P Klein C Schmid AK McCarty KF de la Figuera J 《Physical review letters》2006,96(14):147202
By means of spin-polarized low-energy electron microscopy, we show that the magnetic easy axis of one to three atomic-layer thick cobalt films on Ru(0001) changes its orientation twice during deposition: One-monolayer and three-monolayer thick films are magnetized in plane, while two-monolayer films are magnetized out of plane. The Curie temperatures of films thicker than one monolayer are well above room temperature. Fully relativistic calculations based on the screened Korringa-Kohn-Rostoker method demonstrate that only for two-monolayer cobalt films does the interplay between strain, surface, and interface effects lead to perpendicular magnetization. 相似文献
100.