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71.
Answering a question of M. Talagrand, we show that there is a fixed L with the following property. For positive integers and , if is the set of subgraphs of Kn containing at least copies of Kk, then there is a set of subgraphs of Kn such that (i) each member of contains a member of and (ii) (where means number of edges). © 2014 Wiley Periodicals, Inc. Random Struct. Alg., 47, 663–668, 2015 相似文献
72.
73.
In this paper we have proved a main theorem concerning the | $\bar N$ , p n; δ |k summability methods, which generalizes a result of Bor and Özarslan [3]. 相似文献
74.
一类减算子不动点的存在惟一性定理 总被引:1,自引:0,他引:1
在序Banach空间中利用迭代法证明了一类减算子不动点的存在惟一性,所获结果推广了已知的结论。 相似文献
75.
Marcus Krapp 《Accreditation and quality assurance》2001,6(7):324-326
Recent developments in international trade will have a significant impact on New Zealand’s measurement infrastructure, especially
for chemical metrology. This article describes the background to these developments and outlines the activities of the Measurement
Standards Laboratory, New Zealand’s National Metrology Institute, in response to these developments. 相似文献
76.
Set-indexed martingales and submartingales are defined and studied. The admissible function of a submartingale is defined and some class (D) conditions are given which allow the extension of the function to a -additive measure on the predictable -algebra. Then, we prove a Doob-Meyer decomposition: A set-indexed submartingale can be decomposed into the sum of a weak martingale and an increasing process. A hypothesis of predictability ensures the uniqueness of this decomposition. An explicit construction of the increasing process associated with a submartingale is given. Finally, some remarks, about quasimartingales are discussed.Research supported by a grant from the Natural Sciences and Engineering Research Council of Canada. Dept. of Math. University of Ottawa, Ottawa, Ontario, Canada, K1N 6N5.The third author wishes to thank Professor Ivanoff and Dr. Dozzi for their kind hospitality. Dept. of Math. & Comp. Sci. Bar-Ilan University, Ramat-Gan 52900, Israel. 相似文献
77.
A series of co-crystals of azaaromatic molecule with the present of dicarboxylic acid, [SA·BPE], [FA·AZP], [AA·BPE], [AA·AZP], [SEA·AZP] and [OA·AZP] (BPE=1,2-bis(4-pyridyl)ethylene, AZP=azopyridine, SA=succinic acid, FA=fumaric acid, AA=adipic acid, SEA=sebacic acid, OA=oxalic acid), have been synthesized for the regularity investigation of their supramolecular alignments driven by hydrogen bonding. It is significant for the design and synthesis of supramolecular co-crystals with multiple components. For linear molecules with recognition sites on both ends, the stacking regularity of the molecules in the co-crystals is proposed that the interlaced arrangement (motif III) is preferred when the size of the azaaromatic molecule is comparable with that of dicarboxylic acid and the inclined arrangement (motif II) is adopted when the length of azaaromatic molecule is much different from those of dicarboxylic acids. 相似文献
78.
Three series of MBS core-shell impact modifiers were prepared by grafting styrene and methyl methacrylate onto PB or SBR seed latex in emulsion polymerization. All the MBS modifiers were designed to have the same total chemical composition, and MMA/Bd/St equals 30/42/28, which is a prerequisite for producing transparent blends with PVC. Under this composition, there were three different ways of arrangement for styrene in MBS, which led to the different structure of MBS modifier. The concentration of MBS in PVC/MBS blends was kept at a constant value of 20 wt.%. The effects of arrangement of St in MBS on the mechanical and optical properties of PVC/MBS blends were studied. The notched Izod impact test results showed that the MBS with a PB homopolymer core grafted with St had a lowest brittle-ductile transition (BDT) temperature and BDT temperature increased with the amount of St copolymerized with Bd in the core of MBS. The transparency of blends also increased with the amount of St copolymerized with Bd in the core. TEM results showed that the arrangement of St in MBS influenced the deformation behavior. Two deformation modes were observed in the blends: cavitation and shear yielding. When all St was grafted onto the PB rubber, both cavitation and debonding were observed, which relieve the triaxial tension and promote the shear yielding of the PVC matrix. When all St was copolymerized with Bd in MBS, no cavitation could be observed and only the shear yielding of the PVC matrix took place. 相似文献
79.
80.
A generalization of the Perron‐Frobenius theorem to increasing positively homogeneous of degree one operators is extended to increasing co‐radiant and topical operators, which are of interest in mathematical economics. In particular, small attracting sets containing the limit points of all sequences generated by iteration of such operators are determined. 相似文献