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991.
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Michael J. Blandamer John Burgess Philip P. Duce Robert I. Haines Alexander McAuley 《Transition Metal Chemistry》1982,7(1):10-13
Summary Rate constants are reported for 12-tungstocobaltate(III) [CoW12O40]5– oxidation of iodide in water and in binary aqueous solvent mixtures containing up to 40% methanol, 40% acetonitrile, or 60% dimethyl sulphoxide. From these kinetic results, solubility measurements on potassium 12-tungstocobaltate(III), and published data on Gibbs free energies of transfer of appropriate ions, it has been deduced that the dominant factor in determining the marked decrease in rate observed on going from water into the binary aqueous solvent mixtures is destabilisation of the transition state for the electron-transfer reaction. 相似文献
994.
995.
996.
Carolyn E. M. Morris A. E. Alexander A. G. Parts 《Journal of polymer science. Part A, Polymer chemistry》1966,4(5):985-995
The polymerization of methyl acrylate in water and in dilute, aqueous, soap solutions, initiated by potassium peroxydisulfate, has been investigated, a dilatometric method being used to follow the conversion. It has been shown that small amounts of an anionic soap increase the rate of reaction while a cationic soap has the reverse effect. The change of molecular weight with conversion has also been examined as well as the effect of the exclusion of oxygen from the system. 相似文献
997.
The application of a dissipative Galerkin scheme to the numerical solution of the Korteweg de Vries (KdV) and Regularised Long Wave (RLW) equations, is investigated. The accuracy and stability of the proposed schemes is derived using a localised Fourier analysis. With cubic splines as basis functions, the errors in the numerical solutions of the KdV equation for different mesh-sizes and different amounts of dissipation is determined. It is shown that the Galerkin scheme for the RLW equation gives rise to much smaller errors (for a given mesh-size), and allows larger steps to be taken for the integrations in time (for a specified error tolerance). Also, the interaction of two solitons is compared for the KdV and RLW equations, and several differences in their behaviour are found. 相似文献
998.
The reorientation effect in Coulomb excitation has been used to measure the following static quadrupole moments: . Interference effects from higher excited states have been included in the analysis, with the signs of the E2 matrix elements taken from an anharmonic model. The value obtained for is in disagreement with two previous measurements. We attribute the discrepancy to the smaller internucleon separation distances involved in the previous experiments, which can cause deviations from Coulomb excitation cross sections. The other quadrupole moments have not been measured previously. The B (E2: 0+ → 2+) measured were: . From the angular distribution of the de-excitation γ-rays of the Pb nuclei following recoil into vacuum, we have determined the following (two standard deviations), . Our value of is in agreement with a previous measurement. 相似文献
999.
Mean lifetimes of levels in 22Ne have been measured by the Doppler-shift attenuation method using the inverse reaction 4He(19F, pγ)22Ne. The Doppler-broadened lineshapes observed at 0° were analyzed using scaled experimental stopping powers and give the following results for each of the following levels (energy in keV and lifetime in fs): 4457 ( < 15), 5147 (1300 ± 500), 5522 (27 ± 4), 5641 ( < 20), 6311 (70 ± 10), 6345 ( < 15), 6636 ( < 20) and 6817 ( < 15). The lifetime of the 6311 keV 6+ level is particularly interesting for testing model predictions. The large basis shell model calculations of Preedom and Wildenthal are in good agreement with the experimental B(E2) values for the 2+, 4+ and 6+ members of the ground-state band. 相似文献
1000.