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991.
We investigated the lasing modes of quasi-stadium laser diodes that have confocal cavity geometries, with stripe electrode contacts formed either along the cavity axis or a diamond-shaped trajectory. It was clearly demonstrated that by using narrow electrode contact patterns of 2 μm width, the lowest-order axial and ring modes were excited selectively. On the other hand, the second-lowest-order axial and ring modes were excited by using broad electrode patterns of 14 μm width. Experimentally obtained far-field patterns for lasers with broad and narrow electrode contact patterns agree very well with the simulation results obtained using an extended Fox-Li mode calculation method. 相似文献
992.
Effect of hydrogen introduction into some metal oxide and nitride thin films was examined. Modification of electrical and optical properties by hydrogen introduction was examined on SnO2, Sn–GeO2, Ge–CdO2, ZnO. Electrical resistance could be reduced in some films without loosing their transparence to the visible light. Hydrogen introduction to Cu3N changed the film an electrical conductor. Films of AlN and TiN were rather insensitive to the hydrogen introduction; the hydrogen effect was only observed when the nitrides contain some imperfection in the compounds. 相似文献
993.
The kinetics of diethyl dithiophosphate adsorption on chalcopyrite and tennantite has been studied by UV-visible spectroscopy
at pH values of 4, 6, and 9. The concentration of diethyl dithiophosphate in the solution has been monitored as a function
of time and pH for both minerals. It was found that the adsorption tendency of diethyl dithiophosphate on both minerals decreased
with the increasing pH treatments. This is due to the existence of metal hydroxide species onto the mineral surface in more
alkaline condition inhibiting the adsorption of diethyl dithiophosphate species. In comparison to that of chalcopyrite, tennantite
possessed slightly higher adsorption of diethyl dithiophosphate in acid condition, while vice versa correlation observed at
other pH treatments at where the coverage of metal hydroxide species obtained higher than that of chalcopyrite showing that
the rate oxidation of tennantite is higher. An adsorption mechanism has been proposed and tested against the experimental
kinetic data. Both the kinetic data and flotation studies are consistent with the proposed mechanism. 相似文献
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H. Okamoto 《Journal of Phase Equilibria and Diffusion》2005,26(4):399-399
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1000.
Saida T. Okamoto K. Uchiyama K. Takiguchi K. Shibata T. Sugita A. 《Electronics letters》2001,37(20):1237-1238
An optical digital-to-analogue converter that enables optical pulse pattern recognition, fabricated on the silica-based planar lightwave circuit, is proposed. The converter features an optical transversal filter with a multimode interference combiner. Various kinds of four-bit pulse patterns at 10 Gbit/s have been successfully recognised with the fabricated converter 相似文献