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31.
Zouhair Asfari Jack Harrowfield Pierre Thuéry Jacques Vicens 《Supramolecular chemistry》2013,25(1):69-77
Crystal structure determinations for the hexarubidium and octacesium derivatives of calix[6]arene hexasulfonic acid, as well as of a new solvate of the pentasodium derivative of calix[4]arene tetrasulfonic acid, and comparison with structural data from the literature for alkali metal complexes of sulfonated calixarenes, have provided further evidence for the importance of interactions with aromatic ~ -electrons for the heavier alkali metal cations. There is evidence as well that this interaction can be enhanced by extended ionization of the sulfonated calixarene. 相似文献
32.
Ying Chen Ping Xiang Gang Li Hui-Lan Chen Kandasamy Chinnakali Hoong-Kun Fun 《Supramolecular chemistry》2013,25(4):339-346
The crystal and molecular structures of alkylcobaloxime/ g -cyclodextrin ( g -CD) inclusion complexes: butyl(aqua)cobaloxime/ g -CD ( 1 ). hexyl(aqua)cobaloxime/ g -CD ( 2 ) and cyclohexyl(aqua)cobaloxime/ g -CD ( 3 ) were determined by X-ray diffraction analyses. Crystal data for 1 14H 2 O: P 2 1 2 1 2 1 , a =15.1335(3), b =18.9630(2), c =28.1545(5) Å, Z =4; 2 12H 2 O: P 2 1 2 1 2 1 , a =15.1135(4), b =19.1477(5), c =28.2715(7) Å, Z =4; 3 10H 2 O: P 2 1 2 1 2 1 , a =15.6898(2), b =16.9094(2), c =28.9762(2) Å, Z =4. The structural and conformational comparisons for the three g -CD inclusion complexes with their guest molecules as well as other CD inclusion analogs are discussed. 相似文献
33.
For the specific slip geometry of two sets of coplanar systems (a total of four systems) in fcc metals, the range of dislocation networks in boundaries aligned with one of the two active slip planes is predicted from the Frank equation for boundaries free of long-range elastic stresses. Detailed comparison with experimental data for eight dislocation boundaries in cold-rolled aluminium grains of the 45° ND rotated Cube orientation is conducted. It is concluded that the boundaries are Low-Energy Dislocation Structures, which are in good agreement with the Frank equation while also lowering the energy by dislocation reactions. Cross slip plays a role in the boundary formation process. 相似文献
34.
The $-game 总被引:1,自引:0,他引:1
J. Vitting Andersen D. Sornette 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(1):141-145
We propose a payoff function extending Minority Games (MG) that captures the competition between agents to make money. In
contrast with previous MG, the best strategies are not always targeting the minority but are shifting opportunistically between
the minority and the majority. The emergent properties of the price dynamics and of the wealth of agents are strikingly different
from those found in MG. As the memory of agents is increased, we find a phase transition between a self-sustained speculative
phase in which a “stubborn majority” of agents effectively collaborate to arbitrage a market-maker for their mutual benefit
and a phase where the market-maker always arbitrages the agents. A subset of agents exhibit a sustained non-equilibrium risk-return
profile.
Received 5 June 2002 / Received in final form 21 November 2002 Published online 27 January 2003
RID="a"
ID="a"e-mail: sornette@unice.fr
RID="b"
ID="b"CNRS UMR7536
RID="c"
ID="c"CNRS UMR6622 相似文献
35.
Inevitable self-similar topology of binary trees and their diverse hierarchical density 总被引:1,自引:0,他引:1
K. Paik P. Kumar 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,60(2):247-258
Self-similar topology, which can be characterized
as power law size distribution, has been found in diverse tree
networks ranging from river networks to taxonomic trees. In this
study, we find that the statistical self-similar topology is an
inevitable consequence of any full binary tree organization. We show
this by coding a binary tree as a unique bifurcation string. This
coding scheme allows us to investigate trees over the realm from
deterministic to entirely random trees. To obtain partial random
trees, partial random perturbation is added to the deterministic
trees by an operator similar to that used in genetic algorithms. Our
analysis shows that the hierarchical density of binary trees is more
diverse than has been described in earlier studies. We find that the
connectivity structure of river networks is far from strict
self-similar trees. On the other hand, organization of some social
networks is close to deterministic supercritical trees. 相似文献
36.
R. F.S. Andrade J. G.V. Miranda S. T.R. Pinho T. P. Lobão 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,61(2):247-256
A concept of higher order neighborhood in complex networks,
introduced previously [Phys. Rev. E 73, 046101 (2006)], is systematically
explored to investigate larger scale structures in complex networks. The
basic idea is to consider each higher order neighborhood as a network in
itself, represented by a corresponding adjacency matrix, and to settle a
plenty of new parameters in order to obtain a best characterization of the
whole network. Usual network indices are then used to evaluate the
properties of each neighborhood. The identification of high order
neighborhoods is also regarded as intermediary step towards the evaluation
of global network properties, like the diameter, average shortest path
between node, and network fractal dimension. Results for a large number of
typical networks are presented and discussed. 相似文献
37.
38.
F. F. Gong F. X. Gong F. Y. Gong 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,49(3):267-268
Open dynamic behaviour of financial markets with internal
interactions between agents and with external “fields” from other systems
are investigated using the approach of Grossman and Stiglitz for inefficient
markets, and Keynes for interference of the market using physics of finance
(referred to hereafter as phynance). The simulation results indicate that
the NYSE data analyzed in Plerou, V. et al., Nature 421, 130 (2003) can be fitted
by an equation of order parameter Φ and local deviation R of type:
-(R+0.03) Φ+ 0.6 Φ3 + 0.02 = 0, which is shown to be in
remarkable agreement with Plerou's data. 相似文献
39.
40.
M. Beben A. Orłowski 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,20(4):527-530
Long-time correlations in both well-developed and emerging market indexes are studied. The Hurst exponent as well as detrended
fluctuations analysis (DFA) are used as technical tools. Some features that seem to be specific for developing markets are
discovered and briefly discussed.
Received 17 October 2000 相似文献