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Toluene, as a strong carcinogen, is widely found in the newly renovated rooms, shopping malls, and workshops. Photocatalytic oxidation has great superiority and application prospects for the degradation of toluene. However, low photocatalytic efficiency under visible-light irradiation arising from easy agglomeration of the solid catalysts hinders their photodegradation of toluene gas. In this work, heterostructured TiO2/WO3 photocatalysts were fabricated via an electrospinning technology combining the hydrothermal treatment. The special microstructure and composition allowed the photogenerated electrons quickly transfer from the TiO2 nanofibers to the WO3 nanorods, and thus effectively reduced the recombination of photogenerated electrons and holes. Coupling TiO2 with the narrow band-gap WO3 broadened the spectral response range of TiO2. The heterostructured TiO2/WO3 photocatalysts exhibited a remarkably higher degradation rate of toluene gas than that of the bare TiO2 nanofibers under visible-light irradiation. The photocatalysts were deposited onto the inner walls of the photoreactor and some nylon meshes. The meshes were also placed in the photoreactor in a direction perpendicular to the air flow. The meshes increased the contact between photocatalysts in solid phase and toluene in gas phase, and about 85.3% of the toluene had been degraded in the experimental conditions. [ABSTRACT FROM AUTHOR]

Heterostructured TiO2/SnO2 fibrillar nanocomposites were synthesized by using electrospinning technology with the setup composed of a syringe pump with two parallel syringes on it and a rotating collector. The heterojunctions were formed between TiO2 and SnO2 nanofibers fast and efficiently on a large scale, after the fiberizing carrier polyvinylpyrrolidone (PVP) on the as-spun composite nanofibers was burnt away at 500°C. The samples were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflection spectroscopy (DRS), and photoluminescence spectra (PL), respectively. The results indicated that two kinds of small nanofibers with different diameters were interconnected to form heterojunctions. Photocatalytic tests displayed that the heterostructured TiO2/SnO2 nanofibers exhibited a much higher degradation rate of methylene blue (MB), rhodamine B (RhB), and 4-chlorophenol (4-CP) than that of bare TiO2 nanofibers or Evonik P25 under UV light irradiation. The enhanced photocatalytic activity could be attributed to the effective charge separation derived from the coupling effect of TiO2 and SnO2 nanocomposites. [ABSTRACT FROM AUTHOR]

The article discusses a research study which examined three-dimensional (3D) pharmacophore screening for fentanyl derivatives. The study describes the 3D quantitative structure activity-relationship pharmacophore models generated by the researchers. It discusses the differences in the molecular conformations that resulted in differences in relative analgesic potencies. Comparative molecular field analysis revealed the significant role of steric and electrostatic field interactions.