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301.
Flavio C. Cruz Jorge D. Marconi Arismar Cerqueira S. Jr. Hugo L. Fragnito 《Optics Communications》2010,283(7):1459-1462
We demonstrate broadband second harmonic generation of low-energy pulses produced by injecting two single-frequency lasers into a highly nonlinear fiber. Full nonlinear conversion of the corresponding spectra, consisting of broadband (∼200 nm) optical frequency combs at ∼1580 nm, were obtained by using conventional birefringence phase-matching in two BIBO crystals (2-mm and 100-μm long) with a normal incidence configuration. The crystals were not tilted and the pulses were not compressed. This broadband conversion results from the large phase-matching bandwidth of the nonlinear BIBO crystals at ∼1550 nm, but also seems to be a consequence of a fundamental comb with small spectral phase variation. 相似文献
302.
How much can we tell about flows through networks just from their topological properties? Whereas flow distributions of river basins, trees or cardiovascular systems come naturally to mind, more complex topologies are not so immediate, especially if the network is large and heterogeneously directed. Our study is motivated by the question of how the distribution of path-dependent trails in directed networks is correlated to the distribution of network flows. As an example we have studied the path-dependencies in closed trails in four metropolitan areas in England and the USA and computed their global and spatial correlations with measured traffic flows. We have found that the heterogeneous distribution of traffic intensity is mirrored by the distribution of agglomerate path-dependency and that high traffic roads are packed along corridors at short-to-medium trail lengths from the ensemble of nodes. 相似文献
303.
Measurements are presented of the time-dependent current distribution inside a coaxial electromagnetic plasma gun. The measurements are carried out using an array of six axially distributed dual-Rogowski coils in a balanced circuit configuration. The radial current distributions indicate that operation in the gas-puff mode, i.e., the mode in which the electrode voltage is applied before injection of the gas, results in a stationary ionization front consistent with the presence of a plasma deflagration. The effects of varying the bank capacitance, transmission line inductance, and applied electrode voltage were studied over the range from 14 to 112 μF, 50 to 200 nH, and 1 to 3 kV, respectively. 相似文献
304.
Angelini Flavio Colaneri Katia Herzel Stefano Nicolosi Marco 《Computational Management Science》2021,18(4):539-561
Computational Management Science - We study the optimal asset allocation problem for a fund manager whose compensation depends on the performance of her portfolio with respect to a benchmark. The... 相似文献
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Dr. Natasha Eccles Dr. Flavio della Sala Dr. Bryden A. F. Le Bailly Dr. George F. S. Whitehead Prof. Jonathan Clayden Dr. Simon J. Webb 《ChemistryOpen》2020,9(3):338-345
Two α-aminoisobutyric acid (Aib) foldamers bearing Zn(II)-chelating N-termini have been synthesized and compared with a reported Aib foldamer that has a bis(quinolinyl)/mono(pyridyl) cap (BQPA group). Replacement of the quinolinyl arms of the BQPA-capped foldamer with pyridyl gave a BPPA-capped foldamer, then further replacement of the linking pyridyl with a 1,2,3-triazole gave a BPTA-capped foldamer. Their ability to relay chiral information from carboxylate bound to Zn(II) at the N-terminus to a glycinamide-based NMR reporter of conformational preference at the C-terminus was measured. The importance of the quinolinyl arms became readily apparent, as the foldamers with pyridyl arms were unable to report on the presence of chiral carboxylate in acetonitrile. Low solubility, X-ray crystallography and 1H NMR spectroscopy suggested that interfoldamer interactions inhibited carboxylate binding. However changing solvent to methanol revealed that the end-to-end relay of chiral information could be observed for the Zn(II) complex of the BPTA-capped foldamer at low temperature. 相似文献
308.
Immacolata Tufano Maria Rosaria Iesce Elisabetta Buommino Flavio Cermola 《Natural product research》2020,34(15):2109-2115
AbstractFurolignan-type natural products, possessing important biological properties, have been synthesized from a commercially available furan. The elaborated synthetic strategy is based on an innovative Friedel-Crafts reaction starting from an alcohol or a carboxylic acid and triflic anhydride as promoter. Through this synthetic strategy, furolignans having two different aryl groups have been obtained. The products have been evaluated for their antimicrobial properties on Gram positive and Gram negative bacteria, in order to compare their biological activities with those of natural analogues. 相似文献
309.
Santos Ana Caroline F. Luz Rita C. S. Damos Flavio S. Santana Antônio Euzébio Goulart Pessoa Danilo Galdino Navarro Marcelo Goulart Marilia O. F. 《Journal of Solid State Electrochemistry》2020,24(8):1835-1843
Journal of Solid State Electrochemistry - In this work, the boron-doped diamond electrode (BDDE) was used for the electrocatalytic oxidation of N-acetylcysteine (NAC), in the presence of lipoic... 相似文献