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1.
A polarization-insensitive 40-Gb/s time-division demultiplexer was demonstrated in a polarization-diversity loop configuration. The power penalty was measured to be 2.3 dB at a bit error rates of 10-9 for 10 Gb/s output signals. 相似文献
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The intensity dynamics of the double-clad Yb fibre laser have been characterised. Stabilisation of the fibre laser intensity by using uniform bi-directional pumping is demonstrated. For the single-end-pumped Yb fibre laser, the output becomes more stable for the shorter fibre length due to the higher threshold of stimulated Brillouin scattering, SBS, and Kerr effects and the reduction of saturated absorber effects caused by any unpumped fibre section. By additional pumping in a double-end-pumped configuration, the output power can be scaled higher before detecting high intensity pulses initiated by SBS in the Yb fibre laser due to the reduction of saturable absorption effect. It is confirmed that uniform pumping enhances the stability of the laser output. 相似文献
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Ramnial T McKenzie I Gorodetsky B Tsang EM Clyburne JA 《Chemical communications (Cambridge, England)》2004,(9):1054-1055
One-electron oxidation of N-heterocyclic carbenes (NHCs) has been carried out using oxidising agents such as tetracyanoethylene (TCNE) and ferrocenium [Cp(2)Fe](+); the formation of carbene radical cations is postulated. 相似文献
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Molecular mass distribution of sodium alginate by high-performance size-exclusion chromatography 总被引:8,自引:0,他引:8
Ci SX Huynh TH Louie LW Yang A Beals BJ Ron N Tsang WG Soon-Shiong P Desai NP 《Journal of chromatography. A》1999,864(2):199-210
A sensitive high-performance size-exclusion chromatography (HPSEC) method with simple UV detection was developed for the molecular mass analysis of sodium alginate. It was used to evaluate alginates of varying molecular mass and the results were compared with the viscosity measurements. This HPSEC method was sensitive to serve as the stability indicating method for alginate after storage under different conditions. The information of relative molecular mass distribution of alginate was provided with reference to pullulan molecular mass standards. The comparison of the HPSEC chromatograms of alginate, pullulan and dextran revealed the effect of chemical composition of a polysaccharide and its effect on apparent molecular mass distribution. 相似文献
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A new method in which a series of substituted carbazoles is efficiently produced by the combination of an amide and an arene is described. The key feature of this method is the palladium-catalyzed tandem directed C-H functionalization and amide arylation. The method tolerates substitution on either ring of the biaryl amide substrates, and the products can be assembled in a simple two-step protocol from readily available reagents. The Pd(0) species generated are reoxidized to Pd(II) in the presence of Cu(OAc)2 and an atmosphere of oxygen. 相似文献
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