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121.
Let Q G denote the signless Laplacian matrix of a graph G. An eigenvalue μ of Q G is said to be a main Q-eigenvalue of G if μ has an eigenvector which is not orthogonal to an all-ones vector e. We give some basic properties of main Q-eigenvalues. For a graph G of order n, G is called Q-controllable if G has n distinct main Q-eigenvalues. We show that a graph H is generalized Q-cospectral with a Q-controllable G if and only if H is Q-controllable and there exists a unique rational orthogonal matrix R such that R e = e, Q H = R ? Q G R. 相似文献
122.
Qingying Bu Gerard Buskes Alexey I. Popov Adi Tcaciuc Vladimir G. Troitsky 《Positivity》2013,17(2):283-298
We investigate the relationship between the diagonal of the Fremlin projective tensor product of a Banach lattice E with itself and the 2-concavification of E. 相似文献
123.
trans‐Dichlorotetrapyridineruthenium(II) [trans‐RuCl2(py)4] was synthesized and the structure was determined by single crystal X‐ray crystallography. Highly efficient formation of propylene carbonate (PC) from carbon dioxide and propylene oxide was achieved by using a catalyst system composed of trans‐RuCl2(py)4 and hexadecyl trimethyl ammonium bromide under mild conditions (4h, 80 °C, 3.0 MPa). PC was obtained in nearly 100% selectivity without the formation of a polymer. The catalyst could be recycled constantly many times without any significant loss of its catalytic activity. On the basis of the results, a mechanism for the reaction was proposed. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
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V. Bužek 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1990,17(2):91-100
We study exactly solvable Dicke-like model describing a system of spatially distributed two-level atoms coupled to a single mode cavity field. We study the model in one excitation sub-space, when the field is supposed to be initially in the vacuum state and just one atom of the atomic sample is excited. We show that depending on the particular spatial distribution of atoms the system under consideration can exhibit super-radiation or subradiation. Moreover, we investigate the dynamics of the two-atom system interacting with the cavity field initially prepared in an arbitrary state. Co-operative effects are discussed in this case. 相似文献
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Yifeng Bu Yaquan Wang Yongjie Zhang Li Wang Zhentao Mi 《Reaction Kinetics and Catalysis Letters》2007,90(1):77-84
Ti-MCM-41, B-Ti-MCM-41 and Ti-grafted MCM-41 were synthesized, characterized and studied in the epoxidation of cyclohexene.
The synthetic methods and the effect of water in the oxidant are discussed. 相似文献
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The adsorption of decylmethylsulfoxide (DEMS) onto carbon black and the effects of temperature, salt (NaCl) and acid (HCl) have been measured.Typical two plateaux type adsorption isotherms were obtained. Applying the two step model of surfactant adsorption on solid/liquld interface and the general adsorption isotherm equation[9]the experimental results were interpreted qualitatively and quantitatively. 相似文献