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Highlights: [•] C-doped titanate nanotubes (TNT) are formed through hydrothermal treatment of C-doped TiO2 nanoparticles. [•] The technique is not applicable to the formation of W-doped nanotubes. [•] C-Doped nanotubes absorb into the visible region of the spectrum. [•] TNT materials are more active visible light photocatalysts than their nanoparticulate precursors, and doped materials are more active than non-doped analogues. [•] Improved TNT photoactivity is not reflected in improved photocurrent measurements, reflecting the fact that the nanotubes are disordered. [ABSTRACT FROM AUTHOR]

We have conducted differential water vapour sorption experiments on KevlarTM 49 at 30°C over a series of water vapour pressures from 0 to 90% of saturation, and on the as-polymerised form of the material at 30°C, 45°C and 60°C over a series of water vapour pressures of 0–60%, 0–25% and 0–15%, respectively. The equilibrium isotherms obtained for both samples show a distinct hysteresis-type behaviour. For KevlarTM 49, the hysteresis loop can be divided into two regions, namely above 30%, which is indicative of the presence of microvoids, and below 30%, which suggests inclusion of water into the intimate structure of the surface layer of the polymer crystallites, in a process known as intercalation. [Copyright &y& Elsevier]