Correspondence Author -Tjaart P. J. Krüger, tjaart.kruger@up.ac.za.Abstract-Plasmonic coupling of metallic nanoparticles and adjacent pigments can dramatically increase the brightness of the pigments due to the enhanced local electric field. Here, we demonstrate that the fluorescence brightness of a single plant light-harvesting complex (LHCII) can be significantly enhanced when coupled to single gold nanorods (AuNRs). The AuNRs utilized in this study were prepared via chemical reactions, and the hybrid system was constructed using a simple and economical spin-assisted layer-by-layer technique.Enhancement of fluorescence brightness of up to 240-fold was observed, accompanied by a 109-fold decrease in the average (amplitude-weighted) fluorescence lifetime from approximately 3.5 ns down to 32 ps, corresponding to an excitation enhancement of 63-fold and emission enhancement of up to 3.8-fold. This large enhancement is due to the strong spectral overlap of the longitudinal localized surface plasmon resonance of the utilized AuNRs and the absorption or emission bands of LHCII. This study provides an inexpensive strategy to explore the fluorescence dynamics of weakly emitting photosynthetic light-harvesting complexes at the single molecule level.

Nanostructured zinc oxide synthesized using an easy and low temperature chemical bath deposition method are among the most promising low cost semiconducting nanostructures investigated for a variety of applications. We successfully report the effects of ammonia solution in the growth of ZnO nanorods at a temperature of 60 °C. Successive addition of ammonia altered the degree of supersaturation of the growth solution, causing a significant deviation in the morphology and crystal orientation of ZnO nanorods. Field emission scanning Electron Microscopy images revealed changes in surface morphology of ZnO nanorods with respect to addition of specific amounts of ammonia. X-ray diffraction analysis revealed wurtzite crystal structure of ZnO which was further further supported by X-ray photoelectron studies, optical absorbance and Raman spectra that also revealed the existence of wurtzite ZnO. The current-voltage measurement showed the electrical properties of the synthesized ZnO nanorods. The vertically grown nanorods with flat tops, effect more rectifying Schottky contacts to be realized on comparison to needle like structures.

A surface-wire corona preionized miniature transversely excited atmospheric CO 2 laser was evaluated. The corona pre-ionizer was constructed from alumina (Al 2 O 3 ) ceramic tube and a fine wire stretched along the surface of the tube. When this extremely efficient yet comparatively inexpensive pre-ionizer was applied to the laser, output pulse energy of 230 mJ with a pulse duration of ∼70 ns (FWHM) was obtained from a small discharge volume of 50 cm 3 . This energy output was found to be higher than that obtained from a spark preionized laser with the same discharge volume. Moreover, the discharge stability was also found to improve drastically. These results can therefore be used as a reference when developing full-scale corona pre-ionized laser systems.

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