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851.
Klaus D. Rendulic 《Surface science》1978,70(1):234-238
The potential for a helium atom above field adsorbed helium and neon atoms near a tungsten surface has been calculated. The resulting binding energies at a field of 4.5 V/Å are in the order of 0.03 eV. In addition, the resulting dwelling probabilities for 20 and 80 K are given. 相似文献
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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
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Tridimensional associations of lamellar polymer single crystals, grown from dilute solutions, are described as derived from their sedimentation patterns. These associations include interlocked crystals and decorating crystal halves. The origin of these crystals and their mutual orientation are discussed and tentatively interpreted by specific interactions between the fold surface and the crystallizing chains. 相似文献
859.
Singlet oxygen reacts with 2,5-dimethylthiophene (1) exclusively by (4+2)-cycloaddition to yield the thiaozonide 2. The structure of this product is inferred from its 1H- and 13C NMR spectra. Neat thiaozonide 2 decomposes violently at room temperature. In aprotic non-polar and in protic polar solvents it is slowly transformed into cis-sulfine 3c and cis-2,5-dione 4c, which rearranges to the trans-isomer 4t. A mechanism for the transformation reaction is proposed. 相似文献
860.
The unsaturated ketones 1 – 10 were protonated at low temperatures and studied by dynamic 13C NMR spectroscopy. Four interconverting stereoisomers were detected which differ in their conformation with respect to the CO and CC (enone) single bond. 相似文献