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91.
Thin film tandem solar cells made of amorphous and microcrystalline silicon provide renewable energy at the benefit of low material consumption. As a drawback, these materials do not posses the high carrier mobilities of their crystalline counterpart which limits the feasible material thickness. For maintaining the light absorption as high as possible, photon management is required. Here we show that metallic nanodiscs that sustain localized plasmon polaritons can increase the efficiency of such solar cells if they are incorporated into the dielectric intermediate reflector separating the top and the bottom cell. We provide quantitative estimates for the possible absorption enhancement of optimized bi-periodic nanodiscs that are feasible for fabrication. Emphasis is also put on discussing the impact of obliquely incident sun light on the solar cell performance. 相似文献
92.
Ingo Klimant Falk Ruckruh Gregor Liebsch Achim Stangelmayer Otto S. Wolfbeis 《Mikrochimica acta》1999,131(1-2):35-46
A new type of phenyl substituted ormosils as a matrix for oxygen-sensitive micro-optodes is described. The new ormosils combine
features of classical polymers such as solubility in organic solvents and those of sol–gel glasses such as mechanical stability
and a porous structure. They make possible a simple and fast fabrication of microsensors with reproducible properties. The
influence of the conditions during the polymerisation process (precursor composition and thermal treatment) on the sensing
properties has been studied in detail. Oxygen-sensitive films with ruthenium(II)–tris-(4,7-diphenyl-1,10-phenanthroline) and
platinum(II)–octaethylporphyrin as indicators were characterised with respect to their mechanical and photophysical properties.
Photostability, oxygen sensitivity, response behaviour and signal intensities of the sensing films and the micro-optodes were
examined. Micro-optodes based on the new sensing materials are fast responding, photostable and can be produced with a sufficient
batch to batch reproducibility. Compared to previously described oxygen micro-optodes, where polystyrene was used as immobilisation
matrix, the new sensors can be autoclaved and show favourable properties such as a faster response and a higher sensitivity.
They possess many potential applications in medical and biological research.
Received June 12, 1998. Revision December 10, 1998. 相似文献
93.
94.
K. Bauer H. Falk H. Lehner K. Schlögl U. Wagner 《Monatshefte für Chemie / Chemical Monthly》1970,101(3):941-943
Ohne Zusammenfassung
Concerning the racemization of optically active ferrocene derivatives (short communication)相似文献
95.
96.
Heinz Falk Helmut Marko Norbert Müller Wolfgang Schmitzberger Hugo Stumpe 《Monatshefte für Chemie / Chemical Monthly》1990,121(11):893-901
Summary Apomyoglobin was reconstituted with bile pigments of the verdinoid, 2,3-dihydroverdinoid, pterobilinoid, and violinoid type. Absorption and circular dichroism data as well as formation constants of the complexes were measured. From these results it was concluded that chromophore binding and induced chirality of these pigments are mainly governed by a lipophilic region opposite to the propionic side chain(s) and the asymmetric position of the hydrogen bonding acceptors of the propionic acid side chain(s) at the entrance of the protein pocket.Dedicated to Prof. Dr. A. Eschenmoser on occasion of his 65th birthday 相似文献
97.
98.
99.
Falk Bernsmann Dr. Ovidiu Ersen Dr. Jean‐Claude Voegel Edward Jan Prof. Nicholas A. Kotov Prof. Vincent Ball 《Chemphyschem》2010,11(15):3299-3305
Films formed by oxidation of dopamine are of interest for functionalisation of solid–liquid interfaces owing to their versatility. However, the ability to modulate the properties of such films, for example, permeability to ionic species and the absorption coefficient, is urgently needed. Indeed, melanin films produced by oxidation of dopamine absorb strongly over the whole UV/Vis part of the electromagnetic spectrum and are impermeable to anions even for a film thickness as low as a few nanometers. Herein we combine oxidation of dopamine to produce a solution containing dopamine–melanin particles and their alternating deposition with poly(diallyldimethylammonium chloride) to produce films which have nearly the same morphology as pure dopamine–melanin films but are less compact, more transparent and more permeable to ferrocyanide anions. 相似文献
100.
Adamson P Auty DJ Ayres DS Backhouse C Barr G Bishai M Blake A Bock GJ Boehnlein DJ Bogert D Cavanaugh S Cherdack D Childress S Coelho JA Coleman SJ Corwin L Cronin-Hennessy D Danko IZ de Jong JK Devenish NE Diwan MV Dorman M Escobar CO Evans JJ Falk E Feldman GJ Frohne MV Gallagher HR Gomes RA Goodman MC Gouffon P Graf N Gran R Grant N Grzelak K Habig A Harris D Hartnell J Hatcher R Himmel A Holin A Huang X Hylen J Ilic J Irwin GM Isvan Z Jaffe DE James C Jensen D Kafka T Kasahara SM Koizumi G 《Physical review letters》2011,107(1):011802
Results are reported from a search for active to sterile neutrino oscillations in the MINOS long-baseline experiment, based on the observation of neutral-current neutrino interactions, from an exposure to the NuMI neutrino beam of 7.07×10(20) protons on target. A total of 802 neutral-current event candidates is observed in the Far Detector, compared to an expected number of 754 ± 28(stat) ± 37(syst) for oscillations among three active flavors. The fraction f(s) of disappearing ν(μ) that may transition to ν(s) is found to be less than 22% at the 90% C.L. 相似文献