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131.
Jorge C.G. Calado Edmundo J.S. Gomes de Azevedo Virgílio A.M. Soares Klaus Lucas Keshawa P. Shukla 《Fluid Phase Equilibria》1984,16(2):171-183
The total vapour pressure of the xenon + methyl chloride system has been measured as a function of composition at 175.44 and 182.32 K. The resulting data have been used to evaluate the excess Gibbs functions GE at the same temperatures. The excess enthalpy and excess molar volume have also been measured at 182.32 K. The system shows large positive deviations from Raoult's law but negative volumes on mixing. These results are compared with theoretical predictions of a recent molecular theory and of standard engineering methods. The calculations show the superiority of the molecular theory over more empirical procedures such as those based on the Redlich-Kwong equation of state or the regular-solution model. 相似文献
132.
The nonlinear propagation of an intense circularly polarized electromagnetic wave in a cold plasma is investigated. A relativistic modulational instability and an exact localized solutions are found. 相似文献
133.
Using a molecular perturbation theory based on an equation of state for pure argon, excess properties and vapor-liquid equilibria are predicted for various binary mixtures composed of weakly nonspherical molecules. The results are rather satisfactory and generally much better than obtained using typical empirical methods. It is further demonstrated that a binary parameter in the dispersion energy results in only modest improvement 相似文献
134.
This paper reports conduction mechanism in a-Sb2Se3 over a wide range of temperature (238 to 338 K) and frequency (5 Hz to 100 kHz). The d.c. conductivity measured as a function
of temperature shows semiconducting behaviour with activation energy ΔE=0.42 eV. Thermally induced changes in the electrical and dielectric properties of a-Sb2Se3 have been examined. The a.c. conductivity in the material has been explained using modified CBH model. The band conduction
and single polaron hopping is dominant above room temperature. However, in the lower temperature range the bipolaron hopping
dominates. 相似文献
135.
Chemical correlation studies and application of Horeau's method establish the absolute stereochemistry of the major cadinene from . as shown in {=1}. 相似文献
136.
The self-consistent average-phonon (SCAP) treatment, developed in earlier papers for monoatomic solids was extended to the alkali halides for which self-consistent calculations were not available. The quantitative comparison of SCAP with an average quaiharmonic (AQH) treatment for Ar and for NaCl showed that AQH highly overestimated the thermal pressure. Because of this overestimation, we conclude that the lattice instability reported by Boyer for NaCl, which he considered to be related to melting, is a consequence of using a quasiharmonic approximation. 相似文献
137.
138.
Summary The interaction between dimethyl sulphoxide (DMSO) and water, occurring when the two liquids are mixed together, has been
studied: 1. by the measurement of the rate of migration of the different solvent mixtures, over the whole concentration range,
on paper chromatograms, and 2. by observing the paper chromatographic behaviour of hexacyanoferrate II anions when these mixtures
are used as mobile phases. The rate of migration gives a very pronounced maximum at the solvent concentration which corresponds
to the composition DMSO·H2O. The chromatographic behaviour of the hexacyanoferrate II ion besides confirming this conclusion shows the existence of
three distinct zones of differing solvent structure and solvating behaviour. 相似文献
139.
Dielectric studies in dilute solutions of cyclohexane and benzene have been carried out in the temperature range 294–318°K.
The observed data have been utilized to evaluate the relaxation times and thermodynamic parameters of these molecules. The
high values ofα for 2-acetyl pyridine indicate the occurrence of more than one relaxation time. In the remaining systems, the observed lowα values indicate their rigid behaviour. The variation in the dielectric relaxation time is mostly correlated with the change
in the heterocyclic configuration of the system. 相似文献
140.