Annals of Telecommunications - Le partage du risque est une des raisons les plus souvent avancées pour expliquer les clauses financières des contrats de licence. Pour autant, aucune... 相似文献
Three new azo-benzene-based push-pull chromophores with dendritic architecture were synthesized as active materials for electro-optic applications. These chromophores were synthesized in six or seven synthetic steps with an overall yield of around 80% per step and high purity. UV-vis spectroscopy showed significant influence of the transient dipole moment on the observed r(33) values. The chromophores were stable to photochemical oxidation in ambient light and air. The electrical poling conditions were optimized for each chromophore as the T(g) of the composite material varied significantly. The highest EO coefficient achieved was 22-25 pm/V at 1550 nm wavelength. STEM analysis of the blends enabled the correlation of the activity of these large chromophores with the blend morphology. An amorphous polycarbonate host effectively disperses the chromophores in 2-20 nm aggregates in the active materials. However, macrophase separation into 200-500 nm aggregates was observed in a methacrylate host matrix. 相似文献
The functionalization of zinc oxide (ZnO) nanoparticles by poly(3‐hexylthiophene) (P3HT) brush is completed by the combination of a mussel inspired biomimetic anchoring group and Huisgen cyclo‐addition “click chemistry.” Herein, the direct coupling of an azide modified catechol derivative with an alkyne end‐functionalized P3HT is described. This macromolecular binding agent is used to access core@corona ZnO@P3HT with a stable and homogeneous conjugated organic corona. Preliminary photoluminescence measurement proves an efficient electron transfer from the donor P3HT to the acceptor ZnO nanoparticles upon grafting, thus demonstrating the potential of such a combination in organic electronics.
[reaction: see text] Nucleophilic substitution reactions of racemic and chiral 5-acetoxy-, 5-ethoxy-, and 5-methoxypyrrolidin-2-ones by silicon-based nucleophiles were efficiently catalyzed by TIPSOTf. This process was found to be general and accommodates a broad range of substrate-nucleophile combinations. 相似文献
We demonstrate broadband infrared pulse shaping by difference-frequency mixing of two visible phase-locked linearly chirped pulses in GaAs. Control of the temporal profile of the emitted field is achieved through this direct tailoring of the exciting visible intensity. The results are in agreement with a simulation with no adjustable parameter. 相似文献
Electrochemical intercalation of lithium into multiwall carbon nanotubes produced by the arc-electric technique has been carried
out in button cells to estimate the solid state diffusion coefficients of lithium. An extension of the Galvanostatic Intermittent
Titration Technique (G.I.T.T.) of Weppner and Huggins and further developed by Honders is employed. The results are interpreted
providing that the lithium species enter the nanotubes perpendicularly to their walls and thus give rise to a necklace structure
as observed by Transmission Electron Microscopy (TEM). Finally, the results are compared with the data obtained for different
kinds of carbon: carbon fiber, petroleum coke and graphite.
Paper presented at the 6th Euroconference on Solid State Ionics, Cetraro, Calabria, Italy, Sept. 12–19, 1999. 相似文献