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1.
Tanja Vidaković-Koch Tamara Miličić Luka A. Živković Hoon Seng Chan Ulrike Krewer Menka Petkovska 《Current Opinion in Electrochemistry》2021
The nonlinear frequency response analysis (NFRA) can be seen as an extension of electrochemical impedance spectroscopy. NFRA gives a full and detailed representation of the system response and can establish a connection between model parameters and the experimentally observed phenomena. In this article, different theoretical NFRA approaches and the most recent application examples are discussed. A simple electrochemical example is used to showcase the benefits and disadvantages of analyzing the system response by using different approaches. In addition, it was shown how to extract experimental harmonic values and analyze them. 相似文献
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Efforts are made to explore the hysteresis characteristics of vortex shedding in a pipe flow, whose velocity varies periodically in time. Results obtained show that during acceleration of the flow, the vortex strength tends to be stronger, whereas during deceleration of the flow, the situation is reversed. As reconstructed from the velocity signals measured at a point in the flow field, the shed vortex arrays appear to possess uneven vortex strengths in response to periodically-varying incoming flows. Furthermore, in the hysteresis range, the streamwise spacings between the vortices appear to be unequal. 相似文献
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Past cellular automata models of self-replication have always been initialized with an original copy of the structure that will replicate, and have been based on a transition function that only works for a single, specific structure. This article demonstrates for the first time that it is possible to create cellular automata models in which a self-replicating structure emerges from an initial state having a random density and distribution of individual components. These emergent self-replicating structures employ a fairly general rule set that can support the replication of structures of different sizes and their growth from smaller to larger ones. This rule set also allows “random” interactions of self-replicating structures with each other and with other structures within the cellular automata space. Systematic simulations show that emergence and growth of replicants occurs often and is essentially independent of the cellular space size, initial random pattern of components, and initial density of components, over a broad range of these parameters. The number of replicants and the total number of components they incorporate generally approach quasi-stable values with time. 相似文献
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The deposition of decomposed ethylene on silicon wafer at lower temperature using hot filament chemical vapor deposition (HFCVD) method was applied to compose thin film of carbon and its compounds with silicon and hydrocarbon structures. The films were analyzed using Raman spectroscopy, X-ray diffraction, and scanning electron microscopy with elemental microanalysis by energy dispersive X-ray spectrometer. The structure and morphology of the early stage of the film deposition was analyzed. The obtaining of SiC as well as diamond-like structure with this method and catalytic influence of chemical admixtures on the film structure and properties are discussed. 相似文献
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We present a theoretical analysis of corrugated long-period gratings in planar waveguides. In particular, we calculate the transmission spectra for both the TE and TM polarizations and highlight the polarization-independence conditions. 相似文献
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Tian Chou 《数学年刊B辑(英文版)》1994,15(2):241-246
ANINVARIANCEOFCDFEQUATION¥TIANCHOUAbstract:ThispaperpresentsanewinvariancefortheCDFequation.Usingthisinvariance,theauthorobta... 相似文献