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101.
An electron fluid model is proposed for the lattice dynamics of metals which satisfies the requirement of translational invariance
and the lattice is in equilibrium without recourse to external forces. The model is applied to calculate the phonon dispersion
of sodium in the symmetry directions. 相似文献
102.
Titanium(IV) alkyl xanthates of the types CpTi(S2COR)Cl2, CpTi(S2COR)2Cl and CpTi(S2COR)3, where R = CH3, C2H5, C3H7, C4H9 and C5H11, have been prepared by the reaction of monocyclopentadienyl titanium(IV) trichloride with potassium alkyl xanthates in anhydrous dichloromethane. Conductance and infrared studies suggest that these complexes are non-electrolytes in which all of the xanthate ligands are bidentate. Proton nmr spectra of these complexes indicate that there is rapid rotation of the cyclopentadienyl ring about the metal-ring axis and for the CpTi(S2COR)3 complexes non-equivalence of the alkylxanthate ligands was observed. 相似文献
103.
Photoenolization of a ketone in its lowest triplet state was examined using the AM 1 semiempirical molecular orbital method with complete geometry optimization at the configuration interaction level in the restricted Hartree–Fock frame. The theoretical barrier fits with a polynomial given by Eq. (1) and the probability of tunneling of hydrogen was calculated by the WKB method. The density of states above the zero-point level was estimated by the Whitten–Rabinovitch approximation. Rate constants for the hydrogen and deuterium-abstraction processes via tunneling were then computed at different temperatures. © 1994 John Wiley & Sons, Inc. 相似文献
104.
Four Momentum Transfer between the Fireballs in Carbon-Emulsion Interaction at 4.5 GeV/c per Nucleon
This paper presents an analysis of the four momentum transfer between the fireballs in the events produced in 12C-Emulsion interaction at 4.5 GeV/c per nucleon. The results have been compared with the predications of the Pomeranchuk Pole exchange model. 相似文献
105.
A very important question in ultrarelativistic heavy ion collisions is that of thermalization of the high energy density quark
gluon plasma forud in the central rapidity region. Different approaches have been adopted by various authors to study this
thermalization problem. These include phenomenological string and capacitor plate models, perturbative QCD based parton cascade
models and the classical non-perturbative approach. In this paper we briefly review the earlier studies and discuss our work
which emphasizes the role of non-perturbative collective effects (classical chaos) in the thermalization of the plasma. In
particular, using classical equations of motion of a coloured parton in self-consistent colour fields, we have carried out
a 1+1 dimensional simulation of coloured partonic matter. We find that in certain parameter domains, the system exhibits chaotic
behaviour in non-abelian plasma oscillations, which then leads to thermalization of the plasma. 相似文献
106.
107.
108.
It is shown that the use of realistic charge distribution leads to odd moment dependence of the nuclear field isotope shift. Our expression for field isotope shift reduces to the familiar result of Seltzer for low and moderateZ, Z denoting atomic number. 相似文献
109.
This paper presents a study of the experimental lower boundb
L, on the root-mean-squared impact parameter of the multiparticle production in 70 GeV/c p-nucleon interaction. It has been observed that theb
L decreases with increasing final state multiplicity (n) at this fixed energy. The results are in good agreement with those of other authors.The authors would like to thank Prof. K. D. Tolostov of Dubna, U.S.S.R. for kindly supplying the exposed emulsion plates. 相似文献
110.
The problem considered here is to study the MHD effects on the steady flow of an incompressibe viscous conducting fluid through two concentric porous non-conducting infinite circular cylinders, rotating in various ways with uniform angular velocities in presence of a radial magnetic field. It is supposed that the rate of suction at the inner cylinder is equal to the rate of injection at the outer. 相似文献