GaN/ZnO nanorod light emitting diodes with different emission spectra

Light emitting diodes (LEDs) consisting of p-GaN epitaxial films and n-ZnO nanorods have been fabricated and characterized. The rectifying behavior and emission spectra were strongly dependent on the electronic properties of both GaN film and ZnO nanorods. Light emission under both forward and reverse bias was obtained in all cases, and emission spectra could be changed by annealing the ZnO nanorods. The emission spectra could be further tuned by using a GaN LED epiwafer as a substrate. Both forward and backward diode behavior has been observed and the emission spectra were significantly affected by both the properties of the GaN substrate and the annealing conditions for the ZnO nanorods.

Contribution of an auxin to the uptake of nickel and cadmium in maize seedlings

Maize seedlings were cultured in nickel or cadmium contaminated sand treated with alpha-naphthylacetic acid (NAA). The effects of NAA on nickel and cadmium uptake in roots, shoots, and subcellular fractions (cell wall, nuclei and remained parts of seedling cells) were determined. The data showed growth promotion when NAA was applied at low concentrations and inhibition at high concentrations. Uptake of nickel and cadmium content increased concurrently in roots and shoots. In the subcellular fraction, nickel and cadmium was greatest in the cell wall. The changes in growth had greatest correlation with nickel and cadmium content in the subcellular fraction.