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981.
982.
F. Calogero 《Theoretical and Mathematical Physics》2002,133(2):1445-1454
For a special choice of the three interparticle coupling constants in the three-body version of a many-body problem in the plane that was recently investigated, the general solution of the equations of motion can be written in closed form (and is remarkably simple). We also discuss another analogous three-body problem and obtain two third-order highly nonlinear autonomous ODEs whose general solutions, we conjecture, are entire. In other words, we conjecture that these ODEs feature (a strong version of) the Painlevé property. 相似文献
983.
984.
The conductance of ionic species through a cylindrical nanochannel is explored by means of a mesoscopic lattice Boltzmann numerical method. It is shown that in the absence of any external voltage, the ionic profiles develop a considerable amount of structure within the channel. The details of this structure depend on the ionic density, channel length, and Debye length. In the presence of a trans-membrane electrostatic potential, less structure is observed and Ohm's law is found to hold. 相似文献
985.
986.
Let
be the Haag--Kastler net generated by the
(2) chiral current algebra at level 1. We classify the SL(2,
)-covariant subsystems
by showing that they are all fixed points nets
H
for some subgroup H of the gauge automorphisms group SO(3) of
. Then, using the fact that the net
1 generated by the
(1) chiral current can be regarded as a subsystem of
, we classify the subsystems of
1. In this case, there are two distinct proper subsystems: the one generated by the energy-momentum tensor and the gauge invariant subsystem
. 相似文献
987.
Full quantitative multiple-scattering analysis of X-ray absorption spectra: application to potassium hexacyanoferrat(II) and -(III) complexes 总被引:1,自引:0,他引:1
Hayakawa K Hatada K D'Angelo P Della Longa S Natoli CR Benfatto M 《Journal of the American Chemical Society》2004,126(47):15618-15623
A recently developed method to the full quantitative analysis of the XAS spectra extending from the absorption edge to the high-energy region is presented. This method is based on the use of two independent approaches to the analysis of the EXAFS and XANES data, the well-known GNXAS and the newly developed MXAN procedures. Herein, we report the application of this technique to two iron complexes of known structure where multiple-scattering effects are prominent, the potassium hexacyanoferrat(II) and -(III) crystals and aqueous solutions. The structural parameters obtained from refinements using the two methods are equal and compare quite well with crystallographic values. Small discrepancies between the experimental and calculated XANES spectra have been observed, and their origin has been investigated in the framework of non-muffin-tin correction. The ligand dependence of the theoretical spectra has been also examined. Analysis of the whole energy range of the XAS spectra has been found to be useful in elucidating both the type of ligands and the geometry of iron sites. These results are of particular use in studying the geometrical environment of metallic sites in proteins and complexes of chemical interest. 相似文献
988.
A ditopic palladacycle with SCS pincer coordination, L(PdCl)(2) (1), was isolated and structurally characterized and represents the first example of a transition metal complex with a polythioamide-based macrocycle. Preliminary studies of 1 in the catalytic coupling of 4-iodotoluene and styrene indicated it to be robust in the presence of oxygen and high temperatures, with high turnover numbers in relatively short times. 相似文献
989.
990.