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191.
Use of a thermomechanical analyzer, TMA, affords a rapid, precise method for determining linear expansion coefficients and linear expansivities of cross-linked polymeric insulation material. Completed cable samples were dissassembled and insulation specimens were cut longitudinally and examined with repeated temperature cycling: ethylene—propylene copolymer rubbers and filled and unfilled crosslinked polyethylenes. The TMA results indicated that all specimes were oriented, likely incurred from extrusion processing. The facility of TMA for investigating potential anisotropic behavior from prior orientation is illustrated by examples of TMA measurements on radial specimens, similarly free of mechanical constraints. 相似文献
192.
193.
O(1D), produced from the photolysis of N2O at 2139 Å, reacts with N2O in accord with: We have used the method of chemical difference to obtain an accurate measure of k2/k3 = 0.59 ± 0.01. Furthermore, the quantum yield of production of O(3P), either on direct photolysis or on deactivation of O(1D) by N2O, is less than 0.02 and probably zero. 相似文献
194.
A subset of the stochastically monotone Markov chains has the property that the expectation of unimodal functions of the chain is itself unimodal in the initial state. The variation- diminishing property of TP2 matrices is employed to characterize these Markov chains. Related properties are exhibited. 相似文献
195.
Conclusions We have shown that the transition at 30.5% Fe is a percolation transition with the formation of clusters being correctly described by the accepted model, and that the Mössbauer spectra of a 26.5 at% Fe alloy show evidence of a SDW. Such a SDW with wave vector parallel to a cube axis could provide a preferred direction in an otherwise cubic crystal. 相似文献
196.
197.
Ana Diaz Cristian Mocuta Julian Stangl Mario Keplinger Timm Weitkamp Franz Pfeiffer Christian David Till H. Metzger Günther Bauer 《Journal of synchrotron radiation》2010,17(3):299-307
A study of the coherence and wavefront properties of a pseudo‐channel‐cut monochromator in comparison with a double‐crystal monochromator is presented. Using a double‐grating interferometer designed for the hard X‐ray regime, the complex coherence factor was measured and the wavefront distortions at the sample position were analyzed. A transverse coherence length was found in the vertical direction that was a factor of two larger for the channel‐cut monochromator owing to its higher mechanical stability. The wavefront distortions after different optical elements in the beam, such as monochromators and mirrors, were also quantified. This work is particularly relevant for coherent diffraction imaging experiments with synchrotron sources. 相似文献
198.
Javad Mashreghi Julian Ransford Thomas Ransford 《Journal of Functional Analysis》2018,274(11):3254-3262
We show that every linear functional on the Dirichlet space that is non-zero on nowhere-vanishing functions is necessarily a multiple of a point evaluation. Continuity of the functional is not assumed. As an application, we obtain a characterization of weighted composition operators on the Dirichlet space as being exactly those linear maps that send nowhere-vanishing functions to nowhere-vanishing functions.We also investigate possible extensions to weighted Dirichlet spaces with superharmonic weights. As part of our investigation, we are led to determine which of these spaces contain functions that map the unit disk onto the whole complex plane. 相似文献
199.
For positive integers with , let ICKPD denote a canonical Kirkman packing of order missing one of order . In this paper, it is shown that the necessary condition for existence of an ICKPD, namely , is sufficient with a definite exception , and except possibly when , and . 相似文献
200.
Julian Tugaut 《Comptes Rendus Mathematique》2018,356(6):657-660
It is well-known (see Bolley et al. [3]) that there exists a contraction in Wasserstein distance between the solution to the granular media equation and its unique steady state, provided that the confining potential is strictly convex. Nevertheless, in the nonconvex case, just few is known. In particular, we do not have a unique steady state under easily checked assumptions if the diffusion coefficient is sufficiently small. Consequently, the method of Bolley, Gentil and Guillin can not be applied in this setting. However, here, we present a simple example (for the sake of the simplicity) of a double-well confining potential, and we show the convergence to 0 of the Wasserstein distance between the solution to the granular media equation and a related application (which characterizes the steady states) of this solution. 相似文献