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991.
Molecular‐Level Switching of Polymer/Nanocrystal Non‐Covalent Interactions and Application in Hybrid Solar Cells 下载免费PDF全文
Carlo Giansante Rosanna Mastria Giovanni Lerario Luca Moretti Ilka Kriegel Francesco Scotognella Guglielmo Lanzani Sonia Carallo Marco Esposito Mariano Biasiucci Aurora Rizzo Giuseppe Gigli 《Advanced functional materials》2015,25(1):111-119
Hybrid composites obtained upon blending conjugated polymers and colloidal semiconductor nanocrystals are regarded as attractive photoactive materials for optoelectronic applications. Here it is demonstrated that tailoring nanocrystal surface chemistry permits to control non‐covalent and electronic interactions between organic and inorganic components. The pending moieties of organic ligands at the nanocrystal surface are shown to not merely confer colloidal stability while hindering charge separation and transport, but drastically impact morphology of hybrid composites during formation from blend solutions. The relevance of this approach to photovoltaic applications is demonstrated for composites based on poly(3‐hexylthiophene) and lead sulfide nanocrystals, considered as inadequate until this report, which enable the fabrication of hybrid solar cells displaying a power conversion efficiency that reaches 3%. By investigating (quasi)steady‐state and time‐resolved photo‐induced processes in the nanocomposites and their constituents, it is ascertained that electron transfer occurs at the hybrid interface yielding long‐lived separated charge carriers, whereas interfacial hole transfer appears hindered. Here a reliable alternative aiming to gain control over macroscopic optoelectronic properties of polymer/nanocrystal composites by mediating their non‐covalent interactions via ligands' pending moieties is provided, thus opening new possibilities towards efficient solution‐processed hybrid solar cells. 相似文献
992.
Effect of Heat Treatment and of Primary Austenite Grain Size on the Minimum Size of Detectable Defect on 26NiCrMoV11.5 High Strength Steel 下载免费PDF全文
993.
Franco Concli Carlo Gorla Augusto Della Torre Gianluca Montenegro 《Lubrication Science》2015,27(5):313-326
The increasing need of more and more efficient gearboxes implies the need of predictive models in order to compare, during the design stage, different design solutions. The models provided by literature are mostly experimentally derived and not accurate on real applications. A new trend suggests the adoption of computational fluid dynamics (CFD) for the calculation of the no‐load losses of gear transmissions. In this sense, literature provides some works, but most of them involve only one single phase. In this paper, the real operating condition in which the gears are immersed in an oil lubricant mixture is studied. Adopting an open‐source code, OpenFOAM®, the influence of some operating and geometrical parameters on the churning losses has been investigated. The aims are both to provide data that can be effectively used by engineers in the design practice and to prove, once again, CFD to be an effective approach for this kind of investigations. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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The results of the proficiency test program T062 organised by CNACL (China National Accreditation Committee for Laboratories) were analysed with different statistical procedures: the robust statistic procedure used by the proficiency test organisers and the UNI ISO 5725-2 [8] procedure which is a basic method for the determination of the repeatability and the reproducibility of a standard measurement method to improve the traceability in chemical analysis.The data are taken from a program of chemical analysis on a low alloy steel.The obtained results are commented; the paper aim to give elements of discussion about standard test method, uncertainty evaluations, and repeatability of test results on chemical analysis performed by chemical laboratories. 相似文献
997.
By using first-principles calculations within density functional theory via the local density approximation (LDA) and the generalized-gradient approximation (GGA) of Perdew and Wang for exchange and correlation, we calculate the equilibrium structures of CuO2 and CuO2− clusters. In the case of CuO2, three isomers (OCuO linear and two CuO2 complexes, side-on and bent) lie within 0.5 eV, while the negatively charged cluster is most stable as a linear molecule. Our assignment of measured photo-electron spectra features on the basis of the electronic density of states (EDOS) suggests that the bent structure is the most stable among the two forms of CuO2− complexes. 相似文献
998.
Fabio Affinito Rossella Brunetti Carlo Jacoboni Enrico Piccinini Massimo Rudan Albertino Bigiani Paolo Carloni 《Journal of Computational Electronics》2005,4(1-2):171-174
A physical model and a simulation framework are proposed for the analysis of conduction properties of ion channels. The permeation path of ions along the channel is defined through the simultaneous occupancy of a set of individual ion binding sites within the pore identified from structural X-ray data and Molecular Dynamics (MD) simulations. All permitted elementary transitions between different channel configurations and their rate constants can be evaluated from the atomistic structure and MD data and are implemented into a statistical model which is then coded in a Monte Carlo simulator. Results for K ions permeating the KcsA channel are shown. 相似文献
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