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941.
942.
We observe stable propagation of spatially localized single- and double-charge optical vortices in a self-focusing nonlinear medium. The vortices are created by self-trapping of partially incoherent light carrying a phase dislocation, and they are stabilized when the spatial incoherence of light exceeds a certain threshold. We confirm the vortex stabilization effect by numerical simulations and also show that the similar mechanism of stabilization applies to higher-order vortices. 相似文献
943.
In the photolysis of ketene with benzene in the gas phase, Cycloheptatriene (CHT) and totuene (Tol) have been observed as the products. The ratio, (CHT)/(CHT)+(Tol) are studied at various conditions. The difference of activation energy of formation between toluene and cycloheptariene is evaluated to be 4.76 kcal/mole. 相似文献
944.
A new, thermally initiated hydrogermylation-based method for the synthesis and surface functionalization of air- and moisture-stable germanium quantum dots is reported. 相似文献
945.
946.
947.
Nitric oxide, strongly chemisorbed on ruthenium, is desorbed almost completely as oxygen and nitrogen. Oxygen, nitrogen, and nitric oxide were observed singly on ruthenium with field emission microscopy. Thermal desorption spectroscopy from Ru(101̄0) showed that molecular nitrogen is only physisorbed but nitrogen from NO decomposition is strongly chemisorbed. Nitrogen from NO shows three binding states, the most strongly bound being present to only a small extent. NO shows three and two binding states when adsorbed at 120 K and 295 K respectively. Work function measurements gave Δφ = 1.3 eV for a monolayer of NO. NO is dissociatively adsorbed above 250 K but a lower temperature limit was not established. The decomposition of NO on under high vacuum conditions is catalytic in that no oxides of ruthenium were observed to form in the process. 相似文献
948.
We consider the single-mode Maxwell-Bloch equations describing a Doppler-broadening ring laser. For different parameter ranges this system undergoes period-doubling, intermittency, and two-frequency routes to chaos as a single parameter (e.g., detuning) is varied, as has been observed in recent experiments with He-Ne and He-Xe lasers. 相似文献
949.
950.