The photocatalytic activity of meso-tetraphenylporphyrins with different metal centers (Fe, Co, Mn and Cu) adsorbed on TiO(2) (Degussa P25) surface has been investigated by carrying out the photodegradation of methyl orange (MO) under visible and ultraviolet light irradiation. The photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflectan...

Titanium dioxide (TiO2) is a well-known photocatalyst for environmental cleaning and energy conversion. However, it can only be excited by ultraviolet light for photocatalysis due to its wide band gap (3.2 eV). In this paper, we present a novel (Yb,Er)-NaYF4/C-TiO2 composite which can be perfectly induced not only by ultraviolet light but also weak visible and near infrared lights, owing to the...

We derived the stellar parameters of a sample of Galactic early-O type stars by analysing their UV and Far-UV spectra from FUSE (905-1187Å), IUE, HSTSTIS and ORFEUS (1200-2000Å). The data have been modeled with spherical, hydrodynamic, line-blanketed, non-LTE synthetic spectra computed with the WM-basic code. We obtain effective temperatures ranging from Teff= 41,000 K to 39,000 K for the O3-O4...

We efficiently extract an ultraviolet femtosecond pulse train of milliwatt average power and 100 MHz repetition rate from a colliding pulse mode-locked dye laser by intracavity frequency doubling in KDP. The ultraviolet and visible outputs, which are comparable in power and pulse duration, are perfect synchronized with each

cuals2  chalcopyrite  nanocrystalline  are  synthesized  with  facile method.  the  heat  arrested  solvothermal  method  for  synthesize nanocrystalline  were  investigated.  the  time  duration  of  synthesis, temperature of solution and metal salts to solvent molar ratio can be parameters  that we are  studied. the nanoparticles were  synthesized with cucl, alcl3 and  thiourea (sc(nh2)2) as ...

iii ACKNOWLEDGEMENTS I would like to express my sincere gratitude to all those who provide me with the opportunity to complete this thesis. First, I would like to thank my advisor, Professor Shyh-Chiang Shen, for leading me into this fantastic world of III-nitride electronics, for providing me the intelligence and inspiration during my research, and for teaching me to take my own responsibility...

We report Raman studies of the Si–Si phonon band in Si12xGex alloys, where the excitation is by visible and ultraviolet ~351 nm! light. At a wavelength 351 nm, the optical penetration depth is extremely shallow ~'5 nm!. By varying the excitation from 351 to 514 nm, the optical penetration depth spans from 5 to 300 nm. Two sets of samples were examined. Thin layers grown using molecular beam epi...

A simple dichroic beam splitter capable of separating extreme-ultraviolet (XUV) radiation from high-powered visible and UV laser beams is demonstrated. The device has high XUV reflection efficiency (R approximately 44%) and high damage resistance to intense laser radiation and is therefore applicable to laser-generated XUV radiation sources, including harmonic generation, sum-frequency mixing, ...

The first successful deployment of the fullyoperational ultraviolet rotating shadow-band spectroradiometer occurred during the May 2003 US Department of Energy’s Atmospheric Radiation Measurement program’s Aerosol Intensive Observation Period. The aerosol properties in the visible range were characterized using redundant measurements with several instruments to determine the column aerosol opti...