ZnO quantum dots and KNb3O8 nanosheets were synthesized by a two-step hydrothermal method for the photocatalytic reduction of CO2 to methanol where isopropanol is simultaneously oxidized to acetone . The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), high-resolution transmission electron m...

We compile optical and UV spectra of a sample of ‘typical’ short period black hole X-ray transients in outburst. We also survey determinations of interstellar extinction and distance in order to deredden spectra and compare absolute fluxes. Hence we perform a comparative study of the broad-band spectral energy distributions (SED). We find that given such a homogeneous sample of typical sources,...

We present far-ultraviolet spectra of the Seyfert 1.5 galaxy NGC 5548 obtained in 2000 June with the Far Ultraviolet Spectroscopic Explorer (FUSE). Our data span the observed wavelength range 915–1185 Å at a resolution of ∼ 20 km s. The spectrum shows a weak continuum and emission from O VI λλ1032,1038, C III λ977, and He II λ1085. The FUSE data were obtained when the AGN was in a low state, wh...

Imaging studies have shown that ∼ 25% of LINER galaxies display a compact nuclear UV source. I compare the HST ultraviolet (1150–3200 Å) spectra that are now available for seven such “UVbright” LINERs. The spectra of NGC 404, NGC 4569, and NGC 5055 show clear absorption-line signatures of massive stars, indicating a stellar origin for the UV continuum. Similar features are probably present in N...

The photocatalytic degradation of Procion blue H-B dye in biodegraded textile washwater has been investigated for the complete removal of color and maximum reduction of chemical oxygen demand (COD). Pseudomonas putida was utilized for obtaining biodegraded textile washwater. In this process, silver-doped TiO2 photocatalyst was prepared and experiments were carried out to study the effects of UV...

We present an X–ray/UV/optical spectrum of the black hole primary in the X–ray nova XTE J1118+480 in quiescence at Lx ≈ 4 × 10 LEdd. The Chandra, HST and MMT spectroscopic observations were performed simultaneously on 2002 January 12 UT. Because this 4.1-hr binary is located at b = 62, the transmission of the ISM is very high (e.g., 70% at 0.3 keV). We present many new results for the quiescent...

We present partial-correlation analyses that examine the strengths of the relationships between l2500 Å, l2 keV, αOX, and redshift for optically-selected AGNs. We extend the work of Strateva et al. (2005), that analyzed optically-selected AGNs from the Sloan Digital Sky Survey (SDSS), by including 52 moderate-luminosity, optically-selected AGNs from the COMBO-17 survey with corresponding deep (...

Using the Far Ultraviolet Spectroscopic Explorer (FUSE) we have obtained 87 spectra of 57 low-redshift (z < 0.15) active galactic nuclei (AGN). This sample comprises 53 Type 1 AGN and 4 Type 2. All the Type 1 objects show broad O vi λ1034 emission; two of the Type 2s show narrow O vi emission. In addition to O vi, we also identify emission lines due to C iii λ977, C iii λ991, S iv λλ1062, 1072,...