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71.
72.
The B-spline density-functional method has been applied to the conformers of the (1R, 2R)-1,2-dibromo-1,2-dichloro-1,2-difluoroethane molecule. The cross section, asymmetry, and dichroic parameters relative to core and valence orbitals, which do not change their nature along the conformational curve, have been systematically studied. While the cross section and the asymmetry parameter are weakly affected, the dichroic parameter appears to be rather sensitive to the particular conformer of the molecule, suggesting that this dynamical property could be a useful tool for conformational analysis. The computational method has also been applied to methyl rotation in methyloxirane. Unexpected and dramatic sensitivity of the dichroic-parameter profile to the methyl rotation, both in the core and valence states, has been found. Boltzmann averaging over the conformers reproduces quite closely the profiles previously obtained for the minimum-energy conformation, which is in good agreement with the experimental results. 相似文献
73.
Tommaso Pacini 《Transactions of the American Mathematical Society》2003,355(8):3343-3357
Given a compact Riemannian manifold together with a group of isometries, we discuss MCF of the orbits and some applications: e.g., finding minimal orbits. We then specialize to Lagrangian orbits in Kaehler manifolds. In particular, in the Kaehler-Einstein case we find a relation between MCF and moment maps which, for example, proves that the minimal Lagrangian orbits are isolated.
74.
Ostmark E Macakova L Auletta T Malkoch M Malmström E Blomberg E 《Langmuir : the ACS journal of surfaces and colloids》2005,21(10):4512-4519
In this paper we present results related to the self-assembly of different generations of disulfide-cored 2,2-bis(hydroxymethyl)propionic acid-based dendritic structures onto gold surfaces. These molecular architectures, ranging from generation 1 to generation 3, contain removable acetonide protecting groups at their periphery that are accessible for hydrolysis with subsequent formation of OH-terminated surface-attached dendrons. The deprotection has been investigated in detail as a versatile approach to accomplish reactive surface platforms. A special focus has been devoted to the comparison of the properties of the layers formed by hydrolysis of the acetonide moieties directly on the surface and in solution, prior to the layer formation. 相似文献
75.
76.
We show that the law of propagation of weak discontinuities obtained by A. Jeffrey is in agreement with the Bernoulli's law found by other authors. 相似文献
77.
Abstract In extended thermodynamic the entropy principle and the Galilean invariance dictate respectively constraints for the constitutive
equations and the velocity dependence. The entropy principle in particular requires the existence of a privileged field, the
main field u′, such that the original system becomes symmetric hyperbolic and is generated by four potentials. It is not easy to solve the restrictions of both principles, if we use as field the non convective main
field
and the velocity v. This is due to the fact that
are not independent. Rather its components satisfy three scalar constraints. The aim of this paper is to solve the full problem
using as new strategy to consider
as independent variables and requiring an appropriate differential constraint. This new procedure is very efficient and we
are able to solve the problem of 13 moments in the full non linear case (far from equilibrium). It turns out that the knowledge
of only the equilibrium state function is sufficient to close the system.
Keywords: Extended Thermodynamics, Entropy Principle, Galilean invariance, Rarefied Gas, Hyperbolic systems
Mathematics Subject Classification (2000): 74A20, 76P05, 35l60 相似文献
78.
We present a zero-range pseudopotential applicable for all partial wave interactions between neutral atoms. For p and d waves, we derive effective pseudopotentials, which are useful for problems involving anisotropic external potentials. Finally, we consider two nontrivial applications of the p-wave pseudopotential: we solve analytically the problem of two interacting spin-polarized fermions confined in a harmonic trap, and we analyze the scattering of p-wave interacting particles in a quasi-two-dimensional system. 相似文献
79.
80.
Tommaso Rizzo Alejandro Lage-Castellanos Roberto Mulet Federico Ricci-Tersenghi 《Journal of statistical physics》2010,139(3):375-416
We present a general formalism to make the Replica-Symmetric and Replica-Symmetry-Breaking ansatz in the context of Kikuchi’s
Cluster Variational Method (CVM). Using replicas and the message-passing formulation of CVM we obtain a variational expression
of the replicated free energy of a system with quenched disorder, both averaged and on a single sample, and make the hierarchical
ansatz using functionals of functions of fields to represent the messages. We obtain a set of integral equations for the message
functionals. The main difference with the Bethe case is that the functionals appear in the equations in implicit form and
are not positive definite, thus standard iterative population dynamic algorithms cannot be used to determine them. In the
simplest cases the solution could be obtained iteratively using Fourier transforms. 相似文献