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101.
In this article, we mainly deal with the boundary value problem for harmonic function with values in Clifford algebra: where is a Liapunov surface in , the Dirac operator , are unknown functions with values in a universal Clifford algebra Under some assumptions, we show that the boundary value problem is solvable. 相似文献
102.
《Physics and Chemistry of Liquids》2012,50(4):303-314
Abstract Miscibility of several binary fluid systems, placed in an external gravitational field, has been studied by Molecular Dynamics calculation. The results show inmiscibility and phase separation to appear as a consequence of differences in the Lennard-Jones energy parameter of molecular interaction. Two situations are primarily considered: The case of a big difference in the energy parameters of pure components and the case of a weak interaction between unlike molecules. 相似文献
103.
《代数通讯》2013,41(11):4133-4140
Abstract The aim of this work is to provide characterizations, up to isomorphism, of the standard embedding and the Lister enveloping of an associative pair. We shall obtain it using basic facts on homological algebra. This paper intends to simplify the use of both envelopes. 相似文献
104.
Ajit M Srivastava 《Pramana》2000,55(1-2):53-62
We present a brief review of the subject of disoriented chiral condensates (DCC). We describe the conventional scenarios for
the formation of DCC which have been proposed in the literature. Observable signals, such as fluctuations in neutral to charged
pion ratio, are discussed. We then discuss a novel scenario for DCC formation, recently proposed by us, where the entire region
of hot partons can get converted into a single large DCC. Our arguments suggest that formation of such large DCC is unlikely
in the collision of heavy nuclei, and ultra-high energy hadronic collisions may be better suited for this. 相似文献
105.
We obtain ‘universal’ inequalities for the eigenvalues of the Laplacian acting on differential forms of a Euclidean compact
submanifold. These inequalities generalize the Yang inequality concerning the eigenvalues of the Dirichlet Laplacian of a
bounded Euclidean domain.
相似文献
106.
I Berceanu A Andronic M Duma D MoisĂ M Petrovici A Pop V Simion A del Zoppo G D’Erasmo G Imme G Lanzano A Pagano A Pantaleo G Raciti 《Pramana》1999,53(3):419-424
The excitation function (EF) data for dissipative processes in 19F + 27Al system in the incident energy interval from 113.5 to 130 MeV are used to obtain the dependence of the charge variance and
of the interaction time as a function of the incident energy. Fluctuations are observed in the EFs of both these secondary
observables. Their correlation is supported by a mechanism based on stochastic exchange of nucleons. 相似文献
107.
C. Grimaldi L. Pietronero M. Scattoni 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,10(2):247-255
In the theory of nonadiabatic superconductivity several features are governed by the electron-phonon vertex correction which
has a complex structure both in momentum and frequency. We derive a physical interpretation of such nonadiabatic effects that
permits to link them to specific material properties. We show how the nonadiabatic vertex correction can be decomposed into
two terms with different physical origins. In particular, the first term describes the lattice polarization induced by the
electrons and it is essentially a single-electron process whereas the second term is governed by the particle-hole excitations
due to the exchange part of the phonon-mediated electron-electron interaction. We show that by weakening the influence of
the exchange interaction the vertex takes mostly positive values giving rise to an enhanced effective coupling in the scattering
with phonons. This weakening of the exchange interaction can be obtained by lowering the density of the electrons, or by considering
only long-ranged (small q) electron-phonon couplings.
Received 23 November 1998 and Received in final form 22 January 1999 相似文献
108.
109.
M. Winkelmann G. Fischer B. Pilawa E. Dormann 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,26(2):199-209
Nuclear magnetic resonance (NMR) and relaxation of 63Cu and 65Cu in a powder sample of the heavy-fermion paramagnet CeCu6 is measured and analysed quantitatively. Five different Cu sites are accessible to a detailed analysis. We derive quadrupolar
splitting frequencies, Ce to Cu transferred hyperfine field coupling constants, and transversal as well as longitudinal relaxation
behaviour. Only small relaxation anomalies are observed at the orthorhombic to monoclinic structural phase transition of CeCu6. We point to the different importance of transferred hyperfine interaction and local conduction electron density for static
or dynamic part, respectively, of Cu hyperfine interaction. The different sign of the transferred hyperfine interaction from
Ce3+ to different Cu neighbours reveals the different competing interaction mechanisms, giving rise to the heavy-fermion paramagnetic
behavior of CeCu6.
Received 20 November 2001 相似文献
110.
Alexander Altland 《Annalen der Physik》1994,506(1):28-39
Information about the transport time of electrons through a quasi one-dimensional sample is obtained by calculating the energy auto-correlation function of the conductance. Depending on the length of the sample and its coupling to the external device (here modelled by perfectly conducting leads), the transport time undergoes a smooth crossover between two different limiting regimes. In the case of long samples and good coupling it coincides with the diffusion time. In the opposite limit of short and weakly coupled systems, however, the transport time is given by the reciprocal of the quantum mechanical decay width into the leads. The transition between both regimes is discussed in terms of a few model independent concepts. 相似文献