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961.
962.
963.
964.
The cell rotation graph D(G) on the strongly connected orientations of a 2-edge-connected plane graph G is defined. It is shown that D(G) is a directed forest and every component is an in-tree with one root; if T is a component of D(G), the reversions of all orientations in T induce a component of D(G), denoted by T−, thus (T,T−) is called a pair of in-trees of D(G); G is Eulerian if and only if D(G) has an odd number of components (all Eulerian orientations of G induce the same component of D(G)); the width and height of T are equal to that of T−, respectively. Further it is shown that the pair of directed tree structures on the perfect matchings of a plane elementary bipartite graph G coincide with a pair of in-trees of D(G). Accordingly, such a pair of in-trees on the perfect matchings of any plane bipartite graph have the same width and height. 相似文献
965.
Let D be a set of positive integers. The distance graph G(Z,D) with distance set D is the graph with vertex set Z in which two vertices x,y are adjacent if and only if |x−y|D. The fractional chromatic number, the chromatic number, and the circular chromatic number of G(Z,D) for various D have been extensively studied recently. In this paper, we investigate the fractional chromatic number, the chromatic number, and the circular chromatic number of the distance graphs with the distance sets of the form Dm,[k,k′]={1,2,…,m}−{k,k+1,…,k′}, where m, k, and k′ are natural numbers with m≥k′≥k. In particular, we completely determine the chromatic number of G(Z,Dm,[2,k′]) for arbitrary m, and k′. 相似文献
966.
967.
Krzysztof Chełmiński 《Central European Journal of Mathematics》2003,1(4):670-689
This article defines and presents the mathematical analysis of a new class of models from the theory of inelastic deformations
of metals. This new class, containing so called convex composite models, enlarges the class containing monotone models of
gradient type defined in [1]. This paper starts to establish the existence theory for models from this new class; we restrict
our investigations to the coercive and linear self-controlling case. 相似文献
968.
双KTP内腔参量下转换产生量子相关孪生光子对 总被引:5,自引:2,他引:3
使用双KTP晶体串接,经光学参量振荡腔内参量下转换,在300mW泵浦功率下,获得总功率约23mW的强度相关的孪生光束,在1.25MHz处其强度差噪声功率较散离噪声极限降低50%(3dB)。 相似文献
969.
Under hydrothermal conditions, the reaction of racemic 3‐pyridyl‐3‐aminopropionic acid (rac‐HPAPA) with Eu(ClO4)3· 6H2O affords a 1‐D chain complex, [Eu(3‐PYA)3(H2O)]n ( 1 ) (3‐PYA=3‐pyridylacrylate), which represents an example of neutral 1‐D coordination polymeric material based on 3‐HPYA (HPYA= pyridylacrylic acid) ligand with strong red fluorescent emission in the solid state. 相似文献
970.
Detection of explosives with a fluorescent nanofibril film 总被引:2,自引:0,他引:2
Naddo T Che Y Zhang W Balakrishnan K Yang X Yen M Zhao J Moore JS Zang L 《Journal of the American Chemical Society》2007,129(22):6978-6979