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121.
Judit Ménesi Renáta Kékesi Volker Z?llmer Torben Seemann André Richardt Imre Dékány 《Reaction Kinetics and Catalysis Letters》2009,96(2):367-377
Thin film composites of copper-montmorillonite and TiO2 were prepared and their optical and catalytic properties for ethanol photooxidation were evaluated. The efficiency of composite
Cu-clay/TiO2 = 20/80 was two-fold higher than the standard TiO2(P25) photocatalyst. 相似文献
122.
Torben Prill Dominique Jeulin François Willot Juan Balach Flavio Soldera 《Transport in Porous Media》2017,120(1):141-165
Pore structures have a major impact on the transport and electrical properties of electrochemical devices, such as batteries and electric double-layer capacitors (EDLCs). In this work we are concerned with the prediction of the electrical conductivity, ion diffusivity and volumetric capacitance of EDLC electrodes, manufactured from hierarchically porous carbons. To investigate the dependence of the effective properties on the pore structures, we use a structurally resolved parametric model of a random medium. Our approach starts from 3D FIB-SEM imaging, combined with automatic segmentation. Then, a random set model is fitted to the segmented structures and the effective transport properties are predicted using full field simulations by iterations of FFT on 3D pore space images and calculations based on the geometric properties of the structure model. A parameter study of the model is used to investigate the sensitivity of the effective conductivity and diffusivity to changes in the model parameters. Finally, we investigate the volumetric capacitance of the EDLC electrodes with a geometric model, make a comparison with experimental measurements and do a parameter study to suggest improved microstructures. 相似文献
123.
Nikos Sidiropoulos Sina Hadi Sohi Thomas Lin Pedersen Bo Torben Porse Ole Winther Nicolas Rapin 《Journal of computational and graphical statistics》2018,27(3):673-676
Recent developments in data-driven science have led researchers to integrate data from several sources, over diverse experimental procedures, or databases. This alone poses a major challenge in truthfully visualizing data, especially when the number of data points varies between classes. To aid the representation of datasets with differing sample size, we have developed a new type of plot overcoming limitations of current standard visualization charts. SinaPlot is inspired by the strip chart and the violin plot and operates by letting the normalized density of points restrict the jitter along the x-axis. The plot displays the same contour as a violin plot but resembles a simple strip chart for a small number of data points. By normalizing jitter over all classes, the plot provides a fair representation for comparison between classes with a varying number of samples. In this way, the plot conveys information of both the number of data points, the density distribution, outliers and data spread in a very simple, comprehensible, and condensed format. The package for producing the plots is available for R through the CRAN network using base graphics package and as geom for ggplot through ggforce. We also provide access to a web-server accepting excel sheets to produce the plots (http://servers.binf.ku.dk:8890/sinaplot/). 相似文献
124.
Torben Birk Henning Osholm Srensen Jesper Bendix 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(5):m231-m233
Two new chromium(V)–nitride complexes with a coordination sphere completed by bidentate ligands have been synthesized and structurally characterized. Bis(2‐methylquinolin‐8‐olato)nitridochromium(V), [Cr(C10H8NO)2(N)], has the coordination sphere completed by an equatorial N2O2 set of ligators. The compound crystallizes with the five‐coordinate complexes at sites with twofold rotational symmetry and all Cr—N bond directions aligned with the crystallographic b axis. Nitridobis(2‐sulfidopyridine N‐oxide)chromium(V), [Cr(C5H4NOS)2(N)], crystallizes with the molecules on general positions and has an equatorial S2O2 coordination environment, which is unprecedented among nitride complexes of the first‐row transition metals. In both systems, Cr[triple‐bond]N bonds are short at ca 1.56 Å. 相似文献
125.
126.
Nemeth E Dabelsteen T Pedersen SB Winkler H 《The Journal of the Acoustical Society of America》2006,119(1):620-626
In forests reverberations have probably detrimental and beneficial effects on avian communication. They constrain signal discrimination by masking fast repetitive sounds and they improve signal detection by elongating sounds. This ambivalence of reflections for animal signals in forests is similar to the influence of reverberations on speech or music in indoor sound transmission. Since comparisons of sound fields of forests and concert halls have demonstrated that reflections can contribute in both environments a considerable part to the energy of a received sound, it is here assumed that reverberations enforce also birdsong in forests. Song elements have to be long enough to be superimposed by reflections and therefore longer signals should be louder than shorter ones. An analysis of the influence of signal length on pure tones and on song elements of two sympatric rainforest thrush species demonstrates that longer sounds are less attenuated. The results indicate that higher sound pressure level is caused by superimposing reflections. It is suggested that this beneficial effect of reverberations explains interspecific birdsong differences in element length. Transmission paths with stronger reverberations in relation to direct sound should favor the use of longer signals for better propagation. 相似文献
127.
In isothermal solid mechanics, the space and time domain need to be discretized. This paper presents an approach using high-order finite elements based on Legendre polynomials for the spatial discretization and time-adaptive diagonal-implicit Runge-Kutta methods for the temporal discretization. The superiority of this approach over a traditional one using linear shape functions for the space domain and a Backward-Euler scheme for the time domain is demonstrated. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
128.
Nikolaos Kaplaneris Torben Rogge Rongxin Yin Hui Wang Giedre Sirvinskaite Lutz Ackermann 《Angewandte Chemie (International ed. in English)》2019,58(11):3476-3480
Bioorthogonal C?H allylation with ample scope was accomplished through a versatile manganese(I)‐catalyzed C?H activation for the late‐stage diversification of structurally complex peptides. The unique robustness of the manganese(I) catalysis manifold was reflected by full tolerance of sensitive functional groups, such as iodides, esters, amides, and OH‐free hydroxy groups, thereby setting the stage for the racemization‐free synthesis of C?H fused peptide hybrids featuring steroids, drug molecules, natural products, nucleobases, and saccharides. 相似文献
129.
A class of Fourier Integral Operators which converge to the unitary group of the Schr?dinger equation in the semiclassical
limit ε → 0 in the uniform operator norm is constructed. The convergence allows for an error bound of order O(ε), which can be improved to arbitrary order in ε upon the introduction of corrections in the symbol. On the Ehrenfest-timescale, the result holds with a slightly weaker error
bound. In the chemical literature the approximation is known as the Herman-Kluk propagator. 相似文献
130.
The influence of a tapering on nanowire light-emission profiles is studied. We show that, for nanowires with divergent output beams, the introduction of a conical tapering with a small opening angle reduces the beam divergence and increases transmission. This results in a dramatic increase in the collection efficiency of the detection optics. For a realistic tapering and a modest NA, the collection efficiency is enhanced by more than a factor of 2. This improvement is ensured by the adiabatic expansion of the guided mode in the tapering. 相似文献