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Two functional polyurethanes (P1 and P2) bearing a large π electron conjugated chromophoric pendant were synthesized and characterized by FT-IR, 1H-NMR and UV-Vis absorption spectra. Their optical limiting properties were evaluated. The results show that P1 and P2 show novel optical limiting properties, which are assigned to a long π electron conjugated chromophoric pendant. It was found that their optical limiting properties were affected simultaneously by solution concentration and P2 displays a better optical limiting property than P1 at the same solution transmittance, although that P1 has larger χ(3) (4.28×10-11 esu) than P2 (0.87×10-11 esu), and their optical limiting mechanism is investigated. [ABSTRACT FROM AUTHOR]

Using the organic solvent method, nearly mono-dispersed CdS nanocrystals were obtained in liquid paraffin. The CdS nanocrystals in tetrahedron shape capped with the hydrophobic surfactants in nanometer scale can be assembled to a close-packed mono-layered structure. The CdS nanocrystals with different sizes have been prepared by changing the reaction conditions such as the concentrations of cadmium precursor and sulfur precursor, the initial ratio of Cd:S precursors and the pH value of reaction system. The UV–visible absorption and photoluminescence show the quantum confinement effect clearly. The time-resolved photoluminescence spectra have also been examined. [Copyright &y& Elsevier]

The effect of the number of carbon-fiber-reinforced plastic (CRFP) layers on the axial crushing capacity of aluminum–CFRP square hybrid tubes was investigated both experimentally and numerically. Increasing the number of CRFP layers led to more collapsed lobes and decreased collapsed lobe widths, resulting in an improvement of the energy absorption capacity. The simulation results revealed a distinct tube wall collapse mode in the 4-layer hybrid tubes. The higher bending stiffness of the composite layers in the 4-layer hybrid tube led to debonding of the interface between the aluminum and composite layers. After interface failure, the composite layers did not collapse following the aluminum tube wall and instead rebounded in the approximate longitudinal direction, which directly suffering the longitudinal crushing loading. This behavior led to the shortened plastic collapse width and improvement of the single-layer CFRP energy dissipation due to CFRP delamination. • The effect of CFRP layer number on single-layer CFRP energy absorption was explored. • Different wall collapse mode appeared as CFRP layer number increases. • The increase of CFRP layer number led to decrease of collapse lobe width. • The decrease of collapse lobe width would improve the single-layer CFRP energy absorption. [ABSTRACT FROM AUTHOR]