Nonlinear Lamb waves for fatigue damage identification in FRP-reinforced steel plates.

A nonlinear Lamb-wave-based method for fatigue crack detection in steel plates with and without carbon fibre reinforcement polymer (CFRP) reinforcement is presented in this study. Both numerical simulation and experimental evaluation were performed for Lamb wave propagation and its interaction with a fatigue crack on these two steel plate types. With the generation of the second harmonic, the damage-induced wave nonlinearities were identified by surface-bonded piezoelectric sensors.

Time-resolved surface plasmon polariton coupled exciton and biexciton emission.

We discuss the coupling between optically excited semiconductor nanocrystals (NC) and thin metal films in both the single and multi-exciton regime. Using time-resolved photoluminescence spectroscopy, we determine the decay dynamics of free space and surface plasmon polariton (SPP) coupled emission. The two dynamics are found to be distinctly different at very small NC-metal separations and at photon energies close to the SPP resonance frequency.

Radiative rate enhancements in ensembles of hybrid metal-semiconductor nanostructures.

We report on radiative decay rate modifications of dipole emitters in the proximity of anisotropic metal nanostructures. Using time, angle, and polarization resolved photoluminescence spectroscopy, we show that resonant interactions between surface plasmons in gold nanodisks and excitons in semiconductor nanocrystals require both spectral and orientational overlap resulting in radiative rate enhancements with directional characteristics. Numerical simulations of emission decay dynamics based on local electric field enhancements are in excellent agreement with experimental results.

The capability of glucose toxicity on severe type 2 diabetes.

The underlying defects of type 2 diabetes are impaired insulin sensitivity and decreased beta-cell function. In poorly controlled type 2 diabetes, the 'glucose toxicity' further deteriorates these defects. The objective was to determine whether correction of glucose toxicity will lead to improve insulin sensitivity and beta-cell function in these severely affected patients.