RESUMO
A 5 meter toroidal grating (5m-TGM) beamline has been commissioned to deliver 28 mrad of bending magnet radiation to an ultrahigh vacuum endstation chamber to facilitate angle resolved photoelectron spectroscopy. The 5m-TGM beamline is equipped with Au-coated gratings with 300, 600 and 1200 lines/mm providing monochromatized synchrotron radiation in the energy ranges 25-70 eV, 50-120 eV and 100-240 eV, respectively. The beamline delivers excellent flux (~1014-1017 photons/sec/100mA) and a combined energy resolution of 189 meV for the beamline (at 1.0 mm slit opening) and HA-50 hemispherical analyzer was obtained at the Fermi level of polycrystalline gold crystal. Our preliminary photoelectron spectroscopy results of phenol adsorption on TiO2 (110) surface reveals the metal ion (Ti) oxidation.
RESUMO
The positions of the molecular orbitals of the conjugated semiconducting polymer, poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), relative to the Fermi level, shift when lead selenide (PbSe) quantum dots or the fullerene based molecule [(6)]-1-(3-(methoxycarbonyl)propyl)-[(5)]-1-phenyl-[5,6]-C61, known as PCBM, are dispersed in the polymer host. This is evident from the consistent shifts of occupied molecular orbitals and the valence band edge to greater binding energies and a decrease in density of states near the Fermi level, as probed by photoemission. In the case of PbSe nanocrystal quantum dots, far smaller binding energy shifts were observed. This behavior seems more characteristic of a charge donor, though PbSe and PCBM should act as charge acceptors. In the case of both dopants, what doping does exist occurs only with small concentrations (<10%). MEH-PPV doped with a large-Z semiconducting material, such as PbSe nanocrystal quantum dots, is a candidate for use as a good gamma radiation detector.
RESUMO
We report a case of classical Kaposi's sarcoma involving multiple sites of the penis in a 62-year-old male who was treated with sildenafil citrate-aided electron beam therapy, resulting in complete resolution of the lesions.