2008 NOV 24 - (VerticalNews.com) -- "We demonstrate strong evidence of shape-dependent efficient resonance energy transfer between CdS quantum dots (QDs) and quantum rods (QRs) (donor) to Nile Red dye (acceptor). We also report a simple solution-based method for the preparation of high quality CdS QDs and CdS QRs at relatively low temperature," scientists in Calcutta, India report.

  "The observed quenching of PL intensities are 78.8% and 63.8% for Cds Qds and QRs, respectively in the presence of Nile Red dye. The calculated energy-transfer efficiencies are 45% and 19% from QDs and QRs to dyes, respectively. The energy transfer varies with changing the shape of the nanoparticles. The estimated Forster distances (R-0) are 37.8 and 33.8 angstrom for CdS QDs and QRs, respectively. In the present study, the estimated distances (r) between one donor and one acceptor are 39.1 and 43.1 angstrom for QDs and QRs, respectively using the efficiency of Forester resonance energy transfer (FRET) which depends on the inverse sixth power of the distance of separations between one nanocrystal and one dye molecule. Considering single donor and multiple acceptors interactions, the calculated average distances (r(n)) between the donor and acceptor are 47.7 and 53.9 angstrom for QD's and QR's, respectively," wrote S. Sadhu and colleagues ...read more

  2008 NOV 24 - (VerticalNews.com) -- According to recent research published in the journal Chemphyschem, "Adsorption of poly(rA) on a single-walled carbon nanotube surface in aqueous suspension and the subsequent hybridization of this polymer with free poly(rU) is studied. A comparison of the temperature dependence of the absorbance of free poly (rA) and poly(rA) adsorbed on the nanotube surface [poly(rA)(NT)] at nu(max) = 38 500 cm(-1) shows that the thermostability of the adsorbed polymer is higher. ...read more

  2008 NOV 17 - (VerticalNews.com) -- "Copper doped sodium titanate nanotubes and nanoribbons were prepared via two different doping methods called in situ and ex situ," scientists in Ljubljana, Slovenia report.

  "In the applied in situ method, titanate nanotubes were grown from anatase TiO2 doped with Cu2+, while in the ex situ method, titanate nanotubes and nanoribbons were exposed to aqueous solution of Cu2+ species. By correlating XRD, electron microscopy, magnetic susceptibility, and electron paramagnetic resonance (EPR) measurements, we found that in the samples prepared via the ex situ doping method, sub-10 nm CuO nanoparticles grow on the inner/outer surface of nanotubes/nanoribbons where the Neel transition temperature is strongly suppressed," wrote P. Umek and colleagues ...read more