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991.
Prof. Yuh-Jing Chiou Karol Juchniewicz Krzysztof R. Kupiec Dr. Anna Mikolajczuk-Zychora Dr. Bogusław Mierzwa Prof. Hong-Ming Lin Prof. Andrzej Borodzinski 《ChemElectroChem》2021,8(17):3348-3359
Direct Formic Acid Fuel Cell (DFAFC) is considered as a promising liquid fuel cell. Here, the effect of palladium particle size (dPd) of anodic DFAFC catalysts on initial power density was studied. The number of electrochemically available Pd atoms on the surface of Pd nanocrystallites in the anodes were determined experimentally. The cathode potential as a function of the current density has been measured. The mathematical model describing the effect of dPd on DFAFC performance has been developed. It was assumed that: (i) Pd crystallites have shape of cuboctahedron, (ii) Pd atoms lying on edges and corners are inactive, (iii) The activity of Pd atoms lying on crystallite (111) and (100) facets do not change with dPd. The mathematical model describes well the effect of current density and dPd on fuel cell voltage and power density. The model predicts that maximum power density is reached at dPd=2.4 nm. 相似文献
992.
Marcel Kotora Carsten Buchaly Peter Kreis Andrzej Górak Jozef Markoš 《Chemical Papers》2008,62(1):65-69
A set of experimental data for heterogeneously catalysed esterification of propan-1-ol and propionic acid to propyl propionate
in a pilot scale reactive distillation column is presented. The catalytic section of the column was equipped with the structured
packing Katapak SP-11. Both, rectifying and stripping, sections consisted of the non-reactive structured Sulzer BX packing.
As catalyst, the strongly acidic ion-exchange resin Amberlyst 46 was used. The experimental results show concentration as
well as temperature profiles along the column height and therefore exhibit reliable data for model validation purposes.
Presented at the 34th International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 21–25 May
2007. 相似文献
993.
Mourre method of commutators is used to get low energy resolvent bound for an abstract operatorin a Hilbert space and for a second order variable coefficient elliptic operator in Rd, d?3. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
994.
Marek Borowiec Grzegorz Litak Jacek Hunicz Grzegorz Koszałka Andrzej Niewczas 《PAMM》2008,8(1):10713-10714
We analyze experimental acceleration data obtained from the delivery car vibration test in working conditions. The vertical components of unsprung and sprung mass accelerations have been analyzed by using the Fourier analysis. In particular we examine the response of the sprung mass on various road excitations and conclude the efficiency of the car suspension. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
995.
This work was intended as an attempt to assess the degradation of compressed concrete sample with regard to heterogeneity. The aim of this paper is to estimate of microdamages in heterogeneous materials as such as concrete. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
996.
The paper presents the problem of damage detection basing on the phenomenon of reflection and diffraction of waves at damage boundaries. Elastic waves in plate structures are considered. Damage is modeled as stiffness reduction at a small domain. One‐dimensional discrete signals, representing the velocity or acceleration measured at specified time and plate sections are analyzed using wavelet transform. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
997.
There are some results in the literature showing that Paley graphs behave in many ways like random graphs G(n, 1/2). In this paper, we extend these results to the other family of self‐complementary symmetric graphs. © 2004 Wiley Periodicals, Inc. J Graph Theory 47: 310–316, 2004 相似文献
998.
Given a pair (X, Y) of fixed graphs X and Y, the (X, Y)-intersection graph of a graph G is a graph whose vertices correspond to distinct induced subgraphs of G that are isomorphic to Y, and where two vertices are adjacent iff the intersection of their corresponding subgraphs contains an induced subgraph isomorphic to X. This generalizes the notion of line graphs, since the line graph of G is precisely the (K1, K2)-intersection graph of G. In this paper, we consider the forbidden induced subgraph characterization of (X, Y)-intersection graphs for various (X, Y) pairs; such consideration is motivated by the characterization of line graphs through forbidden induced subgraphs. For this purpose, we restrict our attention to hereditary pairs (a pair (X, Y) is hereditary if every induced subgraph of any (X, Y)-intersection graph is also an (X, Y)-intersection graph), since only for such pairs do (X, Y)-intersection graphs have forbidden induced subgraph characterizations. We show that for hereditary 2-pairs (a pair (X, Y) is a 2-pair if Y contains exactly two induced subgraphs isomorphic to X), the family of line graphs of multigraphs and the family of line graphs of bipartite graphs are the maximum and minimum elements, respectively, of the poset on all families of (X, Y)-intersection graphs ordered by set inclusion. We characterize 2-pairs for which the family of (X, Y)-intersection graphs are exactly the family of line graphs or the family of line graphs of multigraphs. © 1996 John Wiley & Sons, Inc. 相似文献
999.
Hajo Broersma Jiří Fiala Petr A. Golovach Tomáš Kaiser Daniël Paulusma Andrzej Proskurowski 《Journal of Graph Theory》2015,79(4):282-299
We prove that for all an interval graph is ‐Hamilton‐connected if and only if its scattering number is at most k. This complements a previously known fact that an interval graph has a nonnegative scattering number if and only if it contains a Hamilton cycle, as well as a characterization of interval graphs with positive scattering numbers in terms of the minimum size of a path cover. We also give an time algorithm for computing the scattering number of an interval graph with n vertices and m edges, which improves the previously best‐known time bound for solving this problem. As a consequence of our two results, the maximum k for which an interval graph is k‐Hamilton‐connected can be computed in time. 相似文献
1000.
The present paper is the continuation of earlier publications with stack of piezoelectric plates. This work is an author's idea of application for generating characteristics of piezoelectric systems. The presented program, called Piezo3D, allows for generation a single piezoelectric plate graphs as well as complex, free and bonded systems. An additional advantage is the ability to obtain the 3D graphs, in which the characteristics of the test graph can be based not only on frequency, but also on other parameters such as the thickness of the plate. The application is written in the numerical software \"Matlab\". (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献