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161.
We prove that the list chromatic index of a graph of maximum degree Δ and treewidth is Δ; and that the total chromatic number of a graph of maximum degree Δ and treewidth is . This improves results by Meeks and Scott. 相似文献
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G. Beier J. Friese W. Henning P. Kienle H. J. Körner W. Wagner W. A. Mayer W. Mayer 《Zeitschrift für Physik A Hadrons and Nuclei》1990,336(2):217-222
Strongly damped collisions were studied in uranium induced reactions on110Pd and124Sn target nuclei near the barrier. The excitation-energy splitting was deduced from binary reaction yields and those in which the heavy fragment undergoes sequential fission. For systems with 87≦Z≦95 for the heavy fragment, the excitation energy is concentrated in the lighter nucleus, at best shared equally. The results indicate a non-equilibrated energy dissipation, and support nucleon exchange based on average single-particle strength functions as the underlying dissipation mechanism at the barrier. 相似文献
168.
Susanne Bredendiek-Kämper Holger Jenett Henning Bubert Jacek Drozak Bernhard Wielage 《Mikrochimica acta》1990,101(1-6):91-99
This paper reports on the use of Auger electron spectroscopy (AES)/ depth profile analysis for the investigation of plasma-sprayed coatings. Prior to spraying the St 37 substrates are heated to 300 °C or 500 °C for ceramic or metallic layers, respectively. Studies of the starting materials and of the interfaces are important if the adhesion mechanism is to be understood. Therefore the initial components—the unheated and heated substrates and the powder particles NiCrAl, Al2O3 and ZrO2-7.25Y2O3—are analyzed. Depth profiles obtained from two coatings St 37/NiCrAl and St 37/Al2O3 show the influence of plasmaspraying on substrate surfaces and sprayed particles. Plasma-spraying mainly causes a decrease of superficial carbon contamination for both coating layers. In the case of St 37/NiCrAl incorporation of carbon in the sprayed layer is observed. The whole layer is almost completely oxidized except for some areas where substrate and particle material are present. It is assumed that these areas are identical with so-called adherence zones.Dedicated to Professor Günther Tölg on the occasion of his 60th birthday 相似文献
169.
Recently Bezerra, Garcia and Stichtenoth constructed an explicit tower F=(Fn)n?0 of function fields over a finite field Fq3, whose limit λ(F)=limn→∞N(Fn)/g(Fn) attains the Zink bound λ(F)?2(q2−1)/(q+2). Their proof is rather long and very technical. In this paper we replace the complex calculations in their work by structural arguments, thus giving a much simpler and shorter proof for the limit of the Bezerra, Garcia and Stichtenoth tower. 相似文献
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