A facile method to prepare cuprous oxide/bovine serum albumin (Cu 2 O/BSA) hierarchical nanocomposite particles (NCPs) through imitating biomineralization is presented. BSA acted as the structure-directing agents, guiding the nucleation, growth and assembly of Cu(OH) 2 at binding sites to construct the hierarchical structure and then Cu 2 O/BSA NCPs were achieved. The synthesized nanocomposite with hierarchical structure exhibited excellent antibacterial performance. The products obtained were characterized with XRD, TEM, FTIR, EDX and XPS to investigate the formation mechanism of Cu 2 O/BSA hierarchical structure. Cu 2 O/BSA NCPs with size of 20-50 nm built up by several 6-7 nm Cu 2 O nanocrystals with BSA showed better antibacterial performance in the comparative experiments, which was attributed to the special structure and good biocompatibility of the Cu 2 O/BSA NCPs. And the possible mechanism was presented to explain the excellent antibacterial properties of Cu 2 O/BSA NCPs.

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High power, high radiance, broadband light sources emitting in the 2.0-2.5 μm wavelength range are important for optical sensing of biomolecules such as glucose in aqueous solutions. Here we demonstrate and analyze superluminescent diodes with output centered at 2.4 μm (range ~2.2-2.5 μm) from GaInAsSb/AlGaAsSb quantum wells in a separate confinement structure. Pulsed wave output of 1 mW (38 kW/cm2/sr) is achieved at room temperature for 40μm × 2mm devices. Superluminescence is evidenced in superlinear increase in emission, spectral narrowing, and angular narrowing of light output with increasing current injection. Optical output is analyzed and modeled with rate equations. Potential routes for future improvements are explored, such as additional Auger suppression and photonic mode engineering.

Giant magnetostrictive thin films deposited on nonmagnetic substrates can constitute effective sensors and actuators for microdevices. In this work, we investigated the effects of a stress-induced anisotropy on the magnetic properties of Tb0.4Fe0.6, Fe0.5Co0.5 single layer films and [Tb0.4Fe0.6/Fe0.5Co0.5]n multilayers deposited on Si substrates. The magnetostrictive thin films were fabricated by means of RF sputtering and were subjected to a post-deposition annealing treatment. The uniaxial magnetic anisotropy was induced by bending the substrate before deposition and then allowing it to resume its original flat shape after depositing the film. The heat treatment was performed in a vacuum system with a vacuum of 10−6 Torr. The magnetic properties of the fabricated specimens were measured using a SQUID. SEM and XRD analyses were performed to ensure that the thermal treatment would relax the internal stresses induced during the deposition process without crystallizing the film. The thickness of the single layer thin films studied was between 300 and 800 nm while multilayer samples consisted of 6 layers with each layer thickness ranged from about 20 to 40 nm. Compared to single layer samples, multilayer samples with stress anneal growth exhibited an improvement in magnetic saturation by a factor of two while maintaining a low coercive field. Manipulations of the magnitude and direction of magnetic anisotropy was observed by introducing various values of tensile and compressive stress into the film.