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161.
An experimental apparatus and related procedures for the determination of the effective thermal conductivity of sintered powder-metal
plates saturated with distilled water at temperatures in the range 20–150°C are discussed. The apparatus and procedures are
applied to two samples of sintered powder-metal plates, one made of nickel 200 and the other of stainless steel 316, with
porosities of 28.10 and 46.45%, respectively, and each of nominal dimensions 127 mm × 127 mm × 6.35 mm. The experimental
results are compared with corresponding predictions yielded by several correlations available in the literature. The correlations
based on experimental data for packed beds of spherical particles and also porous plates made of cold-pressed (but not sintered)
particles of angular shapes do not apply well to sintered powder-metal plates. A new correlation, which is based on extensions
of ideas contained in earlier works and provides improved predictions, is proposed. 相似文献
162.
163.
S. R. Tuikina 《Computational Mathematics and Modeling》2007,18(1):10-18
We consider a mathematical model of sorption that allows for external diffusion kinetics and a redox reaction. Two inverse
problems are considered for this model, uniqueness is proved, and numerical solution methods are proposed. The efficiency
of the numerical methods is investigated by computer experiments.
__________
Translated from Prikladnaya Matematika i Informatika, No. 23, pp. 15–23, 2006. 相似文献
164.
I. P. Raevskii L. A. Reznichenko M. P. Ivliev V. G. Smotrakov V. V. Eremkin M. A. Malitskaya L. A. Shilkina S. I. Shevtsova A. V. Borodin 《Crystallography Reports》2003,48(3):486-490
(Na, K)NbO3 crystals with a perovskite structure and a KNbO3 content up to 40 mol % were grown from flux with the use of the solvent NaBO2. The dielectric measurements of the crystals grown revealed phase transitions that had never been observed before in ceramic samples. 相似文献
165.
166.
U. Weisbrod R. Gutschke J. Knoth H. Schwenke 《Fresenius' Journal of Analytical Chemistry》1991,341(1-2):83-86
Summary Single layers and layer systems on diverse substrates were measured by Total Reflection X-Ray Fluorescence (TXRF) spectrometry. The angular dependence of the fluorescence intensities at grazing incidence allows the elemental composition, density and thickness of the layers to be evaluated using model calculations. 相似文献
167.
168.
H. Glatzel R. Schneider T. Fauster V. Dose 《Zeitschrift für Physik B Condensed Matter》1992,88(1):53-61
Inverse photoemission spectra were taken for thin epitaxial iron films on Cu(100). For a film thickness of eight monolayers the observed electronic states are characteristic for a fcc(100) surface. Thed-bands of iron show a ferromagnetic exchange splitting of 1.1 eV, considerably smaller than the bulk value of 1.8 eV, which we observe for film thicknesses above 18 monolayers. 相似文献
169.
R. M. Dudley 《Probability Theory and Related Fields》1994,100(2):175-189
Summary In a separable metric space, if two Borel probability measures (laws) are nearby in a suitable metric, then there exist random variables with those laws which are nearby in probability. Specifically, by a well-known theorem of Strassen, the Prohorov distance between two laws is the infimum of Ky Fan distances of random variables with those laws. The present paper considers possible extensions of Strassen's theorem to two random elements one of which may be (compact) set-valued and/or non-measurable. There are positive results in finite-dimensional spaces, but with factors depending on the dimension. Examples show that such factors cannot entirely be avoided, so that the extension of Strassen's theorem to the present situation fails in infinite dimensions.This research was partially supported by a Guggenheim Fellowship, by National Science Foundation grant DMS 8505550 at MSRI-Berkeley, and other NSF grants 相似文献
170.