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891.
The mechanism of ozone formation has been studied using 16O and 18O2. High-resolution microwave spectroscopy was used to measure the amounts of the isotopomeric ozone species formed. The study is hampered by the very rapid exchange process between the reactants, that tends to scramble the isotopes and hence give a 2:1 statistical ratio between the two possible isotopomers. We have found a strategy to come around this difficulty and conclude that the mechanism is a simple end-on-addition. 相似文献
892.
I. N. Ivchenko S. K. Loyalka R. V. Tompson 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2002,25(6):58-72
The slip phenomena in gas mixtures are of fundamental significance in the specification of boundary conditions for flows in the slip regime. In a recent paper, new explicit results for the slip coefficients appropriate to binary gas mixtures were reported. The present work being reported extends the previous work to a higher level of accuracy by involving a higher order Chapman-Enskog expansion. In particular, new expressions for the slip coefficients are presented which are applicable for arbitrary models of the intermolecular interaction. Limiting expressions for the slip coefficients are given (for a simple gas) and the accuracy of the theory is discussed. Numerical calculations of the slip coefficients for different binary gas mixtures using the first and second order Chapman-Enskog approximations and the rigid sphere and Lennard-Jones (12-6) potential models have been carried out. The thermal creep and diffusion slip coefficients are found to be sensitive to the order of the approximation and to the potential model used. A comparison of the new higher order results with some of our previously obtained experimental data for the thermal transpiration effect has also been carried out and shows excellent agreement between the theory and the experiments which confirms the accuracy of the theory. 相似文献
893.
894.
895.
Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Prikladnaya Mekhanika, Vol. 27, No. 1, pp. 50–55, January, 1991. 相似文献
896.
An equation to express ion exchange selectivity coefficient was derived and used for calculating that of PPY film with the results obtained by cyclic voltammetric measurement. PPY film was synthesized by electrochemical method in aqueous solution using K4Fe(CN)6 as supporting electrolyte, and the anions were doped into the film. Ion exchange behaviour of doped Fe (CN)63-/4- in the PPY film with Cl?, NO3? or F? ions in solution has been studied, and the corresponding ion exchange selectivity coefficients were determined. 相似文献
897.
It is shown that using position-sensitive detectors in μSR experiments to determine the muon stopping site in a target permits
one to study correlation effects in μSR time histograms produced by the decay of muons stopping in the same domain, i.e. to
obtain time correlators of μSR histograms of decays from a small region. These correlators contain information on the spatial
correlation of magnetic fields in the sample under study. The proposed method (μSR2-technique) allows measuring correlation radii (r
c
) down to 10−5 cm in a bulk sample. Among interesting physical phenomena occuring overr
c≥3×10−6 cm are, for instance, long wavelength fluctuations of the order parameter near the phase transition point in ferromagnets
and antiferromagnets and magnetic field correlations in magnet domains and spin glasses. One may use this method also on heavy-current
accelerators producing pulsed muon beams to investigate the variation in time of spatial correlations in magnets, spin glasses
and superconductors. 相似文献
898.
N. Gass 《The Journal of the Operational Research Society》1994,45(2):133-142
A methodology is developed to analyse present and future crisis and conflict potentials of small or large geopolitical regions. A set of criteria is used to describe the present economic, social, political and military conditions of a country and the future criteria trends. A multi-criteria decision analysis model is invoked to compute the crisis and conflict potentials under simultaneous consideration of all other countries in that region. The methodology is demonstrated in the crisis and conflict potentials analysis of the former Soviet republics including bordering countries. 相似文献
899.
900.
A potential of mean torque is derived for a solute at infinite dilution in a uniaxial liquid crystal solvent, which contains terms originating from the dispersion interaction, and the electrostatic interaction between quadrupole moments on both molecules. It is shown that the electrostatic term is non-zero only if the solute-solvent vectors are distributed with lower than spherical symmetry. If this distribution has cylindrical symmetry then both the electrostatic and dispersion terms in the potential of mean torque are shown to depend on order parameters for the orientational distribution of the solute-solvent vectors, as well as on the order parameters of the solvent molecules. 相似文献