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991.
992.
The current distribution is investigated theoretically in a shielded superconducting film, which is a film deposited on an insulating superconducting ground plate. An exact result is obtained in the case of a thin and wide film on the basis of London's equation. 相似文献
993.
Benzylaziridine is oxidized anodically in organic solvents. The tetramer (tetra-aza-cyclododecane) is obtained in good yield and the electrical consumption is very low. Authors propose a chain process mechanism in comparison with the chemical method. 相似文献
994.
995.
Gaston Bonnecaze Albert Lichanot Simon Gromb 《Journal of Physics and Chemistry of Solids》1978,39(3):299-310
The study of electrogalvanic and electronic properties of the form β of silver sulfide has been performed on polycrystalline samples whose non stoichiometry is controled by coulometric titration with the cell Ag/RbAg4I5/Ag2+?S/Pt.The data obtained lead to the adoption of an electronic model according to which the Frenkel defects of the silver sublattice are completly ionized. The variation with temperature of the electronic properties near the stoichiometric composition between 23 and 176°C, the temperature of transition between the two forms β and α of Ag2S, enables the forbidden gap Ei = (1,35?1,5 × 10?3T) eV to be computed. The existence range has been drawn between 69°C and the α ? β transition temperature.The study of the ionic conductivity has made it possible to detect two ranges of preferential conduction and to determine the mechanism of migrations of the intersticial silver ions. 相似文献
996.
997.
Albert F. Carley Richard W. Joyner 《Journal of Electron Spectroscopy and Related Phenomena》1978,13(3):411-419
Three cases are presented where X-ray photoelectron spectra generated by an achromatic X-ray source have been deconvoluted by the iterative, Van Cittert method. These are (i the gold 4 f doublet, (ii) the gold valence band, and (iii) the aluminium 2 p spectrum of an oxidized aluminium foil. All prominent features in the deconvolute are shown to be real by comparison with high resolution studies, and the noise levels are low. Resolution after deconvolution is similar to that obtained with a monochromatized X-ray source. The spectra are also similar to those obtained by Fourier transform deconvolution. 相似文献
998.
999.
John F. McGarrity Jacques Prodolliet Timothy Smyth 《Magnetic resonance in chemistry : MRC》1981,17(1):59-65
A system has been designed for the NMR observation (at 60 MHz) of unstable intermediates, with half-lives of 100 ms, at concentration levels above 10?2 M. Rapid mixing can be achieved in less than 40 ms and a series of eight spectra acquired in less than 1.08 s. Low temperature operation is straightforward. Reactive intermediates involved in the reaction of methylamine with 2,4,6,-trinitroanisole and the acid-catalysed hydrolysis of 1,1-diethoxy-2,3-diphenylcycloprop-2-ene were identified, and in a kinetic application, the rate of hydrolysis of trimethyloxonium tetrafluoroborate was measured. 相似文献
1000.
We present a corresponding states analysis of existing data on sound velocity, transport coefficients and intermolecular interaction times of a number of simple fluids. With appropriate choices of parameters for the intermolecular pair potential, such properties as the adiabatic sound velocity, the shear and bulk viscosities, the thermal conductivity and the intermolecular interaction time can be reduced along the liquid-vapor equilibrium curve. Deviations from the simple law of corresponding states are most pronounced for the transport properties, indicating a stronger sensitivity of the dynamical properties to the interaction potential and the molecular structure. 相似文献