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991.
The ultrasonic velocity and density measurements of lanthanum and cerium soaps in a mixture of 60 % benzene and 40 % methanol (v/v) were used to evaluate various acoustic and thermodynamic parameters and to determine the CMC. The results were interpreted in terms of soap-solvent interaction. 相似文献
992.
The question of a possible container shape dependence of the sedimentation velocity in a homogeneous suspension is reexamined. To this end we develop a statistical theory of suspensions based on low-Reynolds-number hydrodynamics of spherical particles in a container. It is shown, to first order in the volume fraction, that in an arbitrary vessel the relative sedimentation velocity is shape independent, but that at the same time shape-dependent convection occurs. The theory forms a bridge between earlier calculations for special geometries by Beenakker and Mazur and a phenomenological theory recently proposed by Nozières.This paper is dedicated to N. G. van Kampen. 相似文献
993.
P. Ruján 《Journal of statistical physics》1982,29(2):247-262
Systems with competing interactions can be often exactly solved on a restricted subspace of the parameter space, called an order or disorder trajectory. A simple method introduced within the transfer matrix formalism allows for the calculation of the free energy and spin-spin correlation functions along the order and disorder lines of the Ising model with all possible interactions around a face of the square lattice (IRF model). The general eight-vertex model is thoroughly examined and shows full analogy with the quantum spin chain results of the previous paper.On leave from and address after September 1, 1982: Institute for Theoretical Physics, Eötvös University, 1088 Budapest, Puskin U. 5–7, Hungary. 相似文献
994.
995.
The one-dimensional Hubbard model with different on-site interaction on the even (Ua) and odd (Ub) sites is considered within the framework of the weak coupling approach. In the case of a 1/4-filled band the dynamical nonequivalence of sites leads to the appearance of Umklapp processes in the system and to the dynamical generation of a commensurability gap in the charge excitation spectrum for Ua ≠ Ub and Ua>0 or Ub>0. Depending on the relation between the bare coupling constants the system shows four different regimes of behaviour in the infrared limit corresponding to normal metal, nonmagnetic insulator, antiferromagnetic insulator and superconducting states. The extended model including interaction between particles on nearest and next-nearest neighbour sites is also considered. 相似文献
996.
J. Seke 《Il Nuovo Cimento D》1993,15(7):1031-1034
Summary By using a self-consistent projection-operator method, developed recently by the present author, a gauge-invariant Markovian
treatment of the spontaneous decay of an unstable atomic state is presented. Without ignoring retardation and electron-spin
effects a gauge-invariant result for the probability amplitude of finding the atom in the unstable state is obtained. 相似文献
997.
The Ising model with competing interactions is studied in a mean field effective medium approach. The phase diagram of such
model alloys is studied. We conclude that for all ratios of the competing interaction moments, a spin glass phase always exists
at low temperatures for certain concentration regimes. 相似文献
998.
Zeno Simon 《Angewandte Chemie (International ed. in English)》1974,13(11):719-727
Specific interactions or recognition processes are extremely important in many fields of chemistry and biology: typical examples are the enzyme-substrate and the antigen-antibody reactions. Quantitative predictions require a knowledge of steric fit, intermolecular forces, and molecular size. These considerations should facilitate design of new drugs. 相似文献
999.
Summary The energy spectrum of sea level muons in the range (102÷104) GeV has been calculated from the latest directly measured JACEE primary spectrum using Fermilab results on pp→π± X and pp→K± X inclusive reactions. The conventional pion atmospheric diffusion equation after Bugaevet al. has been used in this analysis to account the flux of muons emerged from the multiple generation of mesons in air. The derived
muon spectrum has been compared with the earlier magnetic spectrograph data of Durham and Kiel groups. The latest BAKSAN scintillator
telescope data is well in agreement with the calculated integral spectrum originated from the meson decays in the range (1÷104) GeV. 相似文献
1000.
Quantum chromodynamics corrections to orderα
s (the running coupling constant), using the quark-parton approach are calculated for the spin-dependent structure functions
in deep-inelastic polarised electron-nucleon scattering. Consequences of these corrections for the Bjorken sum rule and the
asymmetry in the case of longitudinally polarised (with respect to the beam) nucleons is discussed which could provide possible
tests of quantum chromodynamics. Comparison of our results with the moments of the flavour non-singlet contribution to the
structure functions obtained using operator product expansion is also given.
An erratum to this article is available at . 相似文献