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991.
Claude Leibovici Jean-François Labarre François Crasiner 《Journal of Molecular Structure》1974,23(1):9-13
The electronic structure of SCIF5 is computed within the framework of the CNDO/2 approximation on the basis of Kewley's microwave geometrical data and is compared with our previous results on SF6. The charge distribution and the value of the dipole moment are discussed as a function of the F-S-Fax angle and an inversion of the net charge on Cl is observed when passing through the 95° value for (F-S-Fax) angle. 相似文献
992.
Cross sections for (n, 2n), (n, p), (n, α) and [(n, n′p) + (n, pn)] reactions at 14.7 ± 0.3MeV on enriched 180, 182, 183, 184, 186W isotopes have been measured by the activation technique using Ge(Li) detector γ-ray spectroscopy. Some systematic trends in the cross-section data have been analysed. The (n, 2n) reaction at this energy in this mass region is by far the most favoured reaction and accounts for > 80 % of the total inelastic cross section. 相似文献
993.
994.
995.
Franoise Clouet Jean Brossas 《Journal of polymer science. Part A, Polymer chemistry》1979,17(9):2681-2690
We have prepared model molecules of monohydroxylic and monocarboxylic isoprenic units by initiating isoprene with sec.butyllithium in benzene and killing the living ends by oxygen or carbon dioxide; the monoadduct compounds have been isolated and characterized by nuclear magnetic resonance (NMR) and mass spectrometry. 相似文献
996.
997.
The superconducting transition temperature has been investigated as a function of composition and degree of long-range order in a number of binary and ternary A 15-type phases on Cr and Mo. It is concluded that these compounds are unlike the typical Nb- or V- based phases with the same structure. The maximum Tc does usually not occur at the ideal composition. Nevertheless, a correlation has been found between Tc and the degree of order. 相似文献
998.
François Bayen 《Letters in Mathematical Physics》1979,3(3):161-167
The domain of convergence of the Zassenhaus formula in a Banach algebra is studied. This domain is shown to be strictly larger than the one which was already known. 相似文献
999.
A number of photophysical properties of 5H-dibenzo(a,d) cycloheptene have been measured including the emission and triplet-triplet absorption spectra. The quantum yields and decay parameters for the triplet state of this molecule as a function of temperature have also been measured. The results are discussed and compared to those of molecules. 相似文献
1000.
François Beniere Dimitris Kostopoulos K.V. Reddy 《Journal of Physics and Chemistry of Solids》1980,41(7):727-734
The self-diffusion coefficients of Na+ and I?, as well as the ionic conductivity, are measured in Na(I) single crystals, pure and doped with Ca2+ ions. The computer analysis of the whole set of data shows that the atom transport in Na(I) is ensured essentially by the free vacancies with a very small contribution (~4%) of the vacancy pairs. The thermodynamic parameters of vacancy formation and migration are derived by taking the long range interactions into account (activity coefficients on the concentrations and relaxation factors on the mobilities). The respective entropies of Schottky defect formation, cation migration and anion migration are equal to 7.64, 3.23 and 2.91 k while the corresponding enthalpies are equal to 2.00, 0.58 and 0.77 eV. 相似文献