Some other trivalent rare-earth ions show 5d-4f transitions only in hosts having a wide-band gap energy, and the emission wavelength is in VUV
. A common example is Nd-doped La[F.sub.3], which has an emission wavelength at 175 nm with a few-ns decay time (77) due to the 5d-4f transition of [Nd.sup.3+].
Four different oxidation-based air cleaning technologies were tested: PCO with ozone generating vacuum UV lamps (VUV-PCO), PCO with non-ozone generating UVC lamps (UVC-PCO), ozonation by VUV
lamp, and NTP.
The main objectives of the present study were to (i) compare the removal efficiencies of UV, VUV
, UV/TiO2, VUV/ TiO2 in the presence and absence of dissolved oxygen (ii) to investigate the decomposition kinetics of the applied AOTs and (iii) to investigate the practical applications of the applied AOTs towards removal of pharmaceuticals from wastewater.
Low-pressure mercury lamps of each 0.025 hp (18.4 W) (Ster-L-Ray, Atlantic Ultraviolet Inc.) were employed as an [O.sub.3] source: a G18T5VH/U [O.sub.3]-producing (VUV
) lamp with a maximum emission at 2540 [Angstrom] (254nm) and a minor emission at 1850 [Angstrom] (185nm).
spectroscopy of [Ca.sub.3][Sc.sub.2][Si.sub.3][O.sub.12]:[Pr.sup.3+]: Scintillator optimization by co-doping with [Mg.sup.2+]," ECS Journal of Solid State Science and Technology, Vol.
Zeng et al., "Infrared spectra and VUV
excitation properties of BaLn[B.sub.9][O.sub.16]:Re (Ln = La, Gd; Re = Eu, Tb)," Materials Science and Engineering B, vol.
Costner, et al., Fundamental Optical Properties of Linear and Cyclic Alkanes: VUV
Absorbance and Index of Refraction.
Such unique discharge pattern endows the HFDELs with lots of advantages compared to the conventional UV lamps (i.e., low pressure mercury lamps), including long lifetime of UV output, high UV/vacuum UV (VUV
) radiant power, VUV-mediated generation of [O.sub.3] in conjunction with UV to create hydroxyl radicals (H[O.sup.*]), and adaptable lamp shapes.
Vacuum ultraviolet (VUV
) light has been used in numerous fields, such as cleaning, surface modification, and sterilization, because short wavelength light with high photon energy is capable of breaking strong chemical bonds 1-3].
LYRA [4, 12, 13] is a vacuum ultraviolet (VUV
) solar radiometer.
Wang, "Hydrothermal synthesis and luminescent properties of (La,Gd)PO4:Tb phosphors under VUV
excitation," Materials Letters, vol.
Scintillation light in Argon is emitted in the vacuum ultraviolet (VUV
) region, at 128 nm, from deexcitation of [Ar.sup.*.sub.2] dimers.