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991.
Tetsuo Asaji Janez Seliger Veselko Žagar Hiroyuki Ishida 《Magnetic resonance in chemistry : MRC》2010,48(7):531-536
Proton transfer in hydrogen‐bonded organic co‐crystals of chloranilic acid with some organic bases was investigated by nuclear quadrupole resonance (NQR) spectroscopy. The 35Cl NQR frequencies of chloranilic acid molecule as well as 14N NQR frequencies of the organic base molecule were measured with the conventional pulse methods as well as double‐resonance methods, respectively. The extent of proton transfer in the O···H···N hydrogen bond was estimated from Townes–Dailey analysis of the 14N NQR parameters. The 35Cl NQR frequency and molecular geometry of chloranilic acid are correlated to the extent of proton transfer in the protonation process of the organic base molecule. It is shown that the hydrogen bond affects the π‐electron system of chloranilic acid. Geometry dependence of the O···H···N hydrogen bond, i.e. the H? N valence bond order versus the hydrogen‐bond geometry correlation is also discussed. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
992.
We investigate orthogonal and symplectic bundles with parabolic structure, over a curve. 相似文献
993.
994.
Yoav Yaffe 《Topology and its Applications》2011,158(11):1307-1313
We show that a Polish metric space X which has ‘compact configuration spaces’ is free of almost isometric embeddings, i.e. given such an embedding into X one gets an isometric embedding. By assuming a continuous version of ℵ0-homogeneity we get the converse statement, and also prove almost isometry uniqueness. 相似文献
995.
《Quaestiones Mathematicae》2013,36(3):431-461
AbstractThe author gives a detailed analysis of the relation between the theories of realcompactifications and compactifications in the category of ditopological texture spaces and in the categories of bitopological spaces and topological spaces. 相似文献
996.
997.
《Quaestiones Mathematicae》2013,36(3):333-350
Abstract During my long life I published many papers with related titles. To keep this paper short I will not give proofs and will restrict myself to problems in graph theory, but I will try to give references and make these as complete as possible. I will start with Turk type problems in extremal graph theory. 相似文献
998.
Monotone iterative scheme for nonlinear hyperbolic boundary value problem is established. 相似文献
999.
Koji Katayama 《Journal of Number Theory》2010,130(7):1642-1674
We obtain a “Kronecker limit formula” for the Epstein zeta function. This is done by introducing a generalized gamma function attached to the Epstein zeta function. The methods involve generalizing ideas of Shintani and Stark. We first show that a generalized gamma function appears as the value at s=0 of the first derivative of the associated Epstein zeta function. Then this is used to yield Kronecker's limit formula and its “s=0”-version. 相似文献
1000.
In this paper, a formula of the spectrum of semi-Cayley graphs over finite abelian groups will be given. In particular, the spectrum of Cayley graphs over dihedral groups and dicyclic groups will be given, respectively. 相似文献