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991.
992.
Raoul Mens Fatma Demir Guy Van Assche Bruno Van Mele Dirk Vanderzande Peter Adriaensens 《Journal of polymer science. Part A, Polymer chemistry》2012,50(5):1037-1041
In this article, it is demonstrated that doctor blading of thin poly‐3‐hexylthiophene/phenyl‐C61‐butyric acid methyl ester (1/1) bulk‐hetero junction films from toluene leads to an improved nanocrystallinity, when compared with their unannealed chlorobenzene processed counterparts. This difference in morphology was demonstrated by solid‐state NMR and Rapid Heating Cooling Calorimetry (RHC), being useful complementary techniques to investigate the active layer morphology of photovoltaic devices. An increased PC60BM nanocrystallinity is indicated by several NMR relaxation decay times (T1C, T1H, and T1ρH) and confirmed by an increase of the melting enthalpy in RHC experiments. An improved solar cell performance further strengthens this conclusion. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
993.
994.
995.
Lydia KerschensteinerFlorian Löbermann Wolfgang Steglich Dirk Trauner 《Tetrahedron》2011,67(8):1536-1539
Crocipodin, an unusual benzotropolone pigment, has been isolated from the fruit bodies of the mushroom Leccinum crocipodium. Its structure was determined by spectroscopic methods, particularly 2D NMR spectroscopy. The structure was confirmed by total synthesis, starting from 4-bromocatechol and gallic acid. 相似文献
996.
Nikola Popović Dirk Praetorius Anja Schlömerkemper 《Continuum Mechanics and Thermodynamics》2007,19(1-2):81-109
The analysis of magnetoelastic phenomena is a field of active research. Formulae for the magnetic force in macroscopic systems
have been under discussion for some time. In Popović et al. (Continum. Mech. Thermodyn. 2007), we rigorously justify several
of the available formulae in the context of rigid bodies in two and three space dimensions. In the present, second part of
our study, we investigate these formulae in a series of numerical experiments in which the magnetic force is computed in dependence
on the geometries of the bodies as well as on the distance between them. In case the two bodies are in contact, i.e., in the
limit as their distance tends to zero, we focus especially on a formula obtained in a discrete-to-continuum approximation.
The aim of our study is to help clarify the question which force formula is the correct one in the sense that it describes
nature most accurately and to suggest adequate real-life experiments for a comparison with the provided numerical data.
相似文献
997.
Electronic Structure of the Positive Radical of 13C-Labeled Poly(3-Octylthienylene Vinylene) Polymer
Yun Ling Hanne Diliën Dirk Vanderzande Peter J. Adriaensens Sabine Van Doorslaer 《Applied magnetic resonance》2014,45(9):827-839
Poly(3-octylthienylene vinylene) (O-PTV) has a great potential as low-bandgap p-type semiconductor for photovoltaic applications. Here, the positive radical state (positive polaron) is induced chemically in the O-PTV polymer in which the vinylene sites are selectively 13C-labeled. Using multi-frequency continuous wave and pulsed electron paramagnetic resonance, the g tensor and maximum 1H and 13C hyperfine couplings are determined. A comparative density functional theory (DFT) analysis of PTV-like oligomers is performed. The experimental parameters suggest a larger localization of the positive polaron than follows from the DFT analysis. The counter anion may play a crucial role in localizing the polaron. 相似文献
998.
Tim Brereton Ole Stenzel Björn Baumeier Denis Andrienko Volker Schmidt Dirk Kroese 《Methodology and Computing in Applied Probability》2014,16(2):465-484
A methodology is proposed that is suitable for efficient simulation of continuous-time Markov chains that are nearly-completely decomposable. For such Markov chains the effort to adequately explore the state space via Crude Monte Carlo (CMC) simulation can be extremely large. The purpose of this paper is to provide a fast alternative to the standard CMC algorithm, which we call Aggregate Monte Carlo (AMC). The idea of the AMC algorithm is to reduce the jumping back and forth of the Markov chain in small subregions of the state space. We accomplish this by aggregating such problem regions into single states. We discuss two methods to identify collections of states where the Markov chain may become ‘trapped’: the stochastic watershed segmentation from image analysis, and a graph-theoretic decomposition method. As a motivating application, we consider the problem of estimating the charge carrier mobility of disordered organic semiconductors, which contain low-energy regions in which the charge carrier can quickly become stuck. It is shown that the AMC estimator for the charge carrier mobility reduces computational costs by several orders of magnitude compared to the CMC estimator. 相似文献
999.
Bastian Walter Prashant Saxena Joachim Kaschta Dirk W. Schubert Paul Steinmann 《PAMM》2014,14(1):403-404
Magneto-sensitive elastomers (MSEs) are smart materials changing their shape and mechanical properties in the presence of a magnetic field. Focussing on model systems, silicone based MSEs are prepared by a multi-step mixing process and characterised using a rotational rheometer (plate-plate). Data obtained by relaxation tests is used to set-up a material model coupling the theories of viscoelasticity and magnetoelasticity. The behaviour of MSEs in quasi-static and dynamic mechanical shear experiments can be successfully predicted by the analytical model using parameters received by fitting the transient experiments. The model is validated for small shear deformations (γ = 0.02) and low magnetic fields (𝔹 = 0.2 T). (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
1000.
Sebastian Bauer Patrizio Neff Dirk Pauly Gerhard Starke 《Comptes Rendus Mathematique》2014,352(2):163-166
We present some Poincaré-type inequalities for quadratic matrix fields with applications e.g. in gradient plasticity or fluid dynamics. In particular, applications to the pseudostress–velocity formulation of the stationary Stokes problem and to infinitesimal gradient plasticity are discussed. 相似文献