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981.
The anode supported cell for solid oxide fuel cell, as a modification of the traditional Ni-YSZ anode supported on electrolyte, is examined in this work. The materials obtained on the base of citric method are presented and investigated in this work. The materials consisted of 40 wt.% Ni/YSZ, 50 wt.% Ni/YSZ and 60 wt.% Ni/YSZ were obtained. The base Ni/YSZ materials are tested on the two ways: (a) aging tests and (b) sintering tests. All the materials after aging and sintering are tested by the impedance spectroscopy. The results of electrical conductivity for samples before and after aging show that only in the case of 40 wt.% Ni/YSZ, sample loses of metallic conductivity after 500 h of heating. The other samples reveal metallic conductivity even after long period of aging. The tests of sintering temperature show that this process does not affect significantly on electrical conductivity of the materials. 相似文献
982.
Małgorzata Norek Grzegorz Łuka Marek Godlewski Tomasz Płociński Marta Michalska-Domańska Wojciech J. Stępniowski 《Applied Physics A: Materials Science & Processing》2013,111(1):265-271
Luminescent properties of ZnO nanorods covered with Ag nanoparticles are examined. Nanorods were synthesized on AAO templates using Atomic Layer Deposition (ALD) technique. Two types of the samples were prepared with different arrangement of ZnO nanorods and doping conditions. Nanorods of the second type were codoped with Al, to stimulate defect-related emissions. The ZnO material fills heterogeneously the interior of the AAO nanopores and has hexagonal, wurtzite structure. Both types of structures exhibit a broad defect-related emission at about 440 nm, most probably related to recombination at zinc interstitial (Zni) defects. This emission in samples with a random distribution of ZnO:Al nanorods and finer Ag nanoparticles is enhanced by factor of ~2.5 upon Ag deposition. The so-obtained material is interesting from the point of view of its application in blue range emitting diodes. 相似文献
983.
Summary Analytic equations of the multiconfigurational SCF (MCSCF) response theory are combined with the finite-field (FF) approach to compute static and frequency dependent electric and magnetic properties of the Argon atom. A complete active space (CAS SCF) function including the 3s, 3p, 3d, 4s and 4p orbitals in the active space and a large (17s 13p 7d 5f 3g) basis set are employed. This permits an accurate determination of various linear and non-linear response properties such as e.g. electric dipole polarisability and second hyperpolarisability, Verdet constant, magnetisability and second hyperpolarisability. The results, both for the static values and for the frequency dependence of these properties, compare well with other most recent experimental and theoretical data.Dedicated to Jan Linderberg on the occasion of his 60th birthday 相似文献
984.
We show that it is consistent with MA + ?CH that the Forcing Axiom fails for all forcing notions in the class of ωω–bounding forcing notions with norms of [17].
Received: 28 April 1999 / Published online: 12 December 2001 相似文献
985.
986.
J. Sładkowski 《International Journal of Theoretical Physics》1996,35(10):2075-2083
We investigate how exotic differential structures may reveal themselves in particle physics. The analysis is based on A. Connes'
construction of the standard model. It is shown that, if one of the copies of the spacetime manifold is equipped with an exotic
differential structure, a compact object of geometric origin may exist even if the spacetime is topologically trivial. Possible
implications are discussed. AnSU(3) ⊗SU(2) ⊗U(1) gauge model is constructed. This model may not be realistic, but it shows what kind of physical phenomena might be expected
due to the existence of exotic differential structures on the spacetime manifold. 相似文献
987.
988.
J. Hakl L. Kerekes S. Mészáros K. Vad P. Gurin M. Kis-Varga I. Uzonyi S. Szabó D. L. Beke 《Czechoslovak Journal of Physics》2002,52(2):151-154
Magnetically frozen partially disordered state was observed in nanocrystalline bulk iron prepared by ball-milling of microcrystalline Fe. Role of nanostructure and oxidized fraction is pointed out. Altough we have found a small constituent which is proportional to 1/T in the ZFC curve, the magnetization scaling with T
3/2 at high fields and the hysteretic behavior in FC-ZFC curves signalizes the presence of frozen ferromagnet at low temperatures. 相似文献
989.
Rafał Frański 《Journal of mass spectrometry : JMS》2004,39(3):272-276
The complexes of 2,5-disubstituted-1,3,4-oxadiazoles, namely 2,5-diphenyl-1,3,4-oxadiazole (1), 2,5-bis(2-pyridyl)-1,3,4-oxadiazole (2) and 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (3), with copper cation were studied by electrospray ionization mass spectrometry (ESI-MS). The ability of the compounds studied to form complexes with copper (under the ESI conditions) can be ordered as 2 > 1 > 3. The compounds studied tend to form both 1 : 1 and 2 : 1 chelate complexes with both copper(II) and copper(I). The complexes with copper(I) are formed in the ESI process. The influence of solvent polarity, solution flow-rate, counter ions (Cl−, NO3−, CH3COO−, SO42−, acetylacetonates) on the type of the ions observed was studied. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
990.
E. Grodner A. A. Pasternak Ch. Droste T. Morek J. Srebrny J. Kownacki W. Płóciennik A. A. Wasilewski M. Kowalczyk M. Kisieliński R. Kaczarowski E. Ruchowska A. Kordyasz M. Wolińska 《The European Physical Journal A - Hadrons and Nuclei》2006,27(3):325-340
Lifetimes of yrast levels with spins Iπ = 23/2--43/2- in 131La populated in the 122Sn(14N, 5n) reaction at a beam energy of 70MeV are measured by the Doppler Shift Attenuation method. A model of side-feeding population
is presented. The model parameters are determined in an experiment based on the lineshape of γ-transitions from two highest
spin levels and from the intensity distribution along the yrast band. The properties of the h11/2 band in 131La are compared with the theoretical predictions obtained in the framework of the Core-Quasi-Particle Coupling and the self-consistent
Total Routhian Surface models. 相似文献