47 research outputs found
Maximization of seed yield in transplanted fennel (Foeniculum vulgare Mill.)
A field experiment was conducted at Udaipur (Rajasthan) to study the effect of three plantdensities, four fertilizer treatments and two growth regulators on yield maximization oftransplanted fennel (Foeniculum vulgare). Planting of fennel at a density of 27,770 plants ha-1recorded significantly higher yield attributes (umbels plant-1, seed yield plant-1 and test weight),while seed yield ha-1 was higher with a density of 55,550 plants ha-1 (20.89 q ha-1). Applicationof 90 kg N + 40 kg P2O5 + 20 kg K2O + 20 kg S + 5 kg Zn ha-1 recorded significantly higher yieldattributes and yield of fennel during both the years. Application of naphthalene acetic acid100 ppm recorded significantly higher yield attributes and seed yield.
 
Annealed Silver-Island Films for Applications in Metal-Enhanced Fluorescence: Interpretation in Terms of Radiating Plasmons
The effects of thermally annealed silver island films have been studied with regard to their potential applicability in applications of metal-enhanced fluorescence, an emerging tool in nano-biotechnology. Silver island films were thermally annealed between 75 and 250°C for several hours. As a function of both time and annealing temperature, the surface plasmon band at ≈420 nm both diminished and was blue shifted. These changes in plasmon resonance have been characterized using both absorption measurements, as well as topographically using Atomic Force Microscopy. Subsequently, the net changes in plasmon absorption are interpreted as the silver island films becoming spherical and growing in height, as well as an increased spacing between the particles. Interestingly, when the annealed surfaces are coated with a fluorescein-labeled protein, significant enhancements in fluorescence are osbserved, scaling with annealing temperature and time. These observations strongly support our recent hypothesis that the extent of metal-enhanced fluorescence is due to the ability of surface plasmons to radiate coupled fluorophore fluorescence. Given that the extinction spectrum of the silvered films is comprised of both an absorption and scattering component, and that these components are proportional to the diameter cubed and to the sixth power, respectively, then larger structures are expected to have a greater scattering contribution to their extinction spectrum and, therefore, more efficiently radiate coupled fluorophore emission. Subsequently, we have been able to correlate our increases in fluorescence emission with an increased particle size, providing strong experiment evidence for our recently reported metal-enhanced fluorescence, facilitated by radiating plasmons hypothesis