Dye Sensitized Solar Cells: Maybe Organic Chemistry isn’t that bad after all.
Dye Sensitized Solar Cells (DSSCs) are photovoltaic structures that may replace standard silicon solar cells due to their ease of construction and lower cost. Ruthenium Dye structures, such as N3 (ruthenium (2,2' bipyridyl-4,4' dicarboxylate)2 (NCS)2), have shown the most promise for collection efficiencies near silicon photovoltaic levels. Altering the ligands on the Ruthenium molecules affects the energies of light that are absorbed by the DSSC. Conventional photovoltaic testing, including current versus voltage tests, of these dyes in DSSCs with both narrow LED light sources and broadband (AM1.5 solar simulator) allows comparison between maximum efficiency, fill-factor, short-circuit current, open circuit voltage, and wavelength dependence of efficiency for the dye molecules.
Detecting Fissionable Materials Using High-Energy Prompt Neutrons
Idaho State University
Department of Physics
The neutron emission energy spectra were measured for several targets immediately following activation by pulsed bremsstrahlung photon beams. Spectra were measured using a neutron time-of-flight spectrometer at various bremmstrahlung endpoint energies between 6 and 20 MeV. While fission neutrons can be emitted with energies in excess of 10 MeV, photoneutron emissions from nonfissionable materials are dependant upon binding and incident particle energies. Hence a simple energy discrimination of neutron emissions can be employed to detect the presence of fissionable materials.